1
|
Berube B, Ernst E, Cahn J, Roche B, de Santis Alves C, Lynn J, Scheben A, Grimanelli D, Siepel A, Ross-Ibarra J, Kermicle J, Martienssen RA. Teosinte Pollen Drive guides maize diversification and domestication by RNAi. Nature 2024:10.1038/s41586-024-07788-0. [PMID: 39112710 DOI: 10.1038/s41586-024-07788-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 07/04/2024] [Indexed: 08/17/2024]
Abstract
Selfish genetic elements contribute to hybrid incompatibility and bias or 'drive' their own transmission1,2. Chromosomal drive typically functions in asymmetric female meiosis, whereas gene drive is normally post-meiotic and typically found in males. Here, using single-molecule and single-pollen genome sequencing, we describe Teosinte Pollen Drive, an instance of gene drive in hybrids between maize (Zea mays ssp. mays) and teosinte mexicana (Z. mays ssp. mexicana) that depends on RNA interference (RNAi). 22-nucleotide small RNAs from a non-coding RNA hairpin in mexicana depend on Dicer-like 2 (Dcl2) and target Teosinte Drive Responder 1 (Tdr1), which encodes a lipase required for pollen viability. Dcl2, Tdr1 and the hairpin are in tight pseudolinkage on chromosome 5, but only when transmitted through the male. Introgression of mexicana into early cultivated maize is thought to have been critical to its geographical dispersal throughout the Americas3, and a tightly linked inversion in mexicana spans a major domestication sweep in modern maize4. A survey of maize traditional varieties and sympatric populations of teosinte mexicana reveals correlated patterns of admixture among unlinked genes required for RNAi on at least four chromosomes that are also subject to gene drive in pollen from synthetic hybrids. Teosinte Pollen Drive probably had a major role in maize domestication and diversification, and offers an explanation for the widespread abundance of 'self' small RNAs in the germ lines of plants and animals.
Collapse
Affiliation(s)
- Benjamin Berube
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Evan Ernst
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Jonathan Cahn
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Benjamin Roche
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | | | - Jason Lynn
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Armin Scheben
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | | | - Adam Siepel
- Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Jeffrey Ross-Ibarra
- Department of Evolution and Ecology, Center for Population Biology and Genome Center, University of California at Davis, Davis, CA, USA
| | - Jerry Kermicle
- Laboratory of Genetics, University of Wisconsin, Madison, WI, USA
| | - Robert A Martienssen
- Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
| |
Collapse
|
2
|
Wang Z, Xia A, Wang Q, Cui Z, Lu M, Ye Y, Wang Y, He Y. Natural polymorphisms in ZMET2 encoding a DNA methyltransferase modulate the number of husk layers in maize. PLANT PHYSIOLOGY 2024; 195:2129-2142. [PMID: 38431291 PMCID: PMC11213254 DOI: 10.1093/plphys/kiae113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/30/2024] [Accepted: 02/08/2024] [Indexed: 03/05/2024]
Abstract
DNA methylation affects agronomic traits and the environmental adaptability of crops, but the natural polymorphisms in DNA methylation-related genes and their contributions to phenotypic variation in maize (Zea mays) remain elusive. Here, we show that a polymorphic 10-bp insertion/deletion variant in the 3'UTR of Zea methyltransferase2 (ZMET2) alters its transcript level and accounts for variation in the number of maize husk layers. ZMET2 encodes a chromomethylase and is required for maintaining genome-wide DNA methylation in the CHG sequence context. Disruption of ZMET2 increased the number of husk layers and resulted in thousands of differentially methylated regions, a proportion of which were also distinguishable in natural ZMET2 alleles. Population genetic analyses indicated that ZMET2 was a target of selection and might play a role in the spread of maize from tropical to temperate regions. Our results provide important insights into the natural variation of ZMET2 that confers both global and locus-specific effects on DNA methylation, which contribute to phenotypic diversity in maize.
Collapse
Affiliation(s)
- Zi Wang
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Aiai Xia
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Qi Wang
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| | - Zhenhai Cui
- Shenyang Key Laboratory of Maize Genomic Selection Breeding, Shenyang Agricultural University, Shenyang 110866, China
| | - Ming Lu
- Maize Research Institute, Jilin Academy of Agricultural Sciences, Gongzhuling 136100, China
| | - Yusheng Ye
- Maize Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang 110065, China
| | - Yanbo Wang
- Maize Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang 110065, China
| | - Yan He
- State Key Laboratory of Maize Bio-breeding, National Maize Improvement Center of China, China Agricultural University, Beijing 100094, China
| |
Collapse
|
3
|
Rodrigues MF, Kern AD, Ralph PL. Shared evolutionary processes shape landscapes of genomic variation in the great apes. Genetics 2024; 226:iyae006. [PMID: 38242701 PMCID: PMC10990428 DOI: 10.1093/genetics/iyae006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 10/26/2023] [Accepted: 01/03/2024] [Indexed: 01/21/2024] Open
Abstract
For at least the past 5 decades, population genetics, as a field, has worked to describe the precise balance of forces that shape patterns of variation in genomes. The problem is challenging because modeling the interactions between evolutionary processes is difficult, and different processes can impact genetic variation in similar ways. In this paper, we describe how diversity and divergence between closely related species change with time, using correlations between landscapes of genetic variation as a tool to understand the interplay between evolutionary processes. We find strong correlations between landscapes of diversity and divergence in a well-sampled set of great ape genomes, and explore how various processes such as incomplete lineage sorting, mutation rate variation, GC-biased gene conversion and selection contribute to these correlations. Through highly realistic, chromosome-scale, forward-in-time simulations, we show that the landscapes of diversity and divergence in the great apes are too well correlated to be explained via strictly neutral processes alone. Our best fitting simulation includes both deleterious and beneficial mutations in functional portions of the genome, in which 9% of fixations within those regions is driven by positive selection. This study provides a framework for modeling genetic variation in closely related species, an approach which can shed light on the complex balance of forces that have shaped genetic variation.
Collapse
Affiliation(s)
- Murillo F Rodrigues
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA
- Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Andrew D Kern
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA
- Department of Biology, University of Oregon, Eugene, OR 97403, USA
| | - Peter L Ralph
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, USA
- Department of Biology, University of Oregon, Eugene, OR 97403, USA
- Department of Mathematics, University of Oregon, Eugene, OR 97403, USA
| |
Collapse
|
4
|
Matheson J, Masel J. Background Selection From Unlinked Sites Causes Nonindependent Evolution of Deleterious Mutations. Genome Biol Evol 2024; 16:evae050. [PMID: 38482769 PMCID: PMC10972689 DOI: 10.1093/gbe/evae050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2024] [Indexed: 04/01/2024] Open
Abstract
Background selection describes the reduction in neutral diversity caused by selection against deleterious alleles at other loci. It is typically assumed that the purging of deleterious alleles affects linked neutral variants, and indeed simulations typically only treat a genomic window. However, background selection at unlinked loci also depresses neutral diversity. In agreement with previous analytical approximations, in our simulations of a human-like genome with a realistically high genome-wide deleterious mutation rate, the effects of unlinked background selection exceed those of linked background selection. Background selection reduces neutral genetic diversity by a factor that is independent of census population size. Outside of genic regions, the strength of background selection increases with the mean selection coefficient, contradicting the linked theory but in agreement with the unlinked theory. Neutral diversity within genic regions is fairly independent of the strength of selection. Deleterious genetic load among haploid individuals is underdispersed, indicating nonindependent evolution of deleterious mutations. Empirical evidence for underdispersion was previously interpreted as evidence for global epistasis, but we recover it from a non-epistatic model.
Collapse
Affiliation(s)
- Joseph Matheson
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
- Department of Ecology, Behavior, and Evolution, University of California San Diego, San Diego, CA 92093, USA
| | - Joanna Masel
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
| |
Collapse
|
5
|
Schmidt SB, Brown LK, Booth A, Wishart J, Hedley PE, Martin P, Husted S, George TS, Russell J. Heritage genetics for adaptation to marginal soils in barley. TRENDS IN PLANT SCIENCE 2023; 28:544-551. [PMID: 36858842 DOI: 10.1016/j.tplants.2023.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 01/17/2023] [Accepted: 01/23/2023] [Indexed: 05/22/2023]
Abstract
Future crops need to be sustainable in the face of climate change. Modern barley varieties have been bred for high productivity and quality; however, they have suffered considerable genetic erosion, losing crucial genetic diversity. This renders modern cultivars vulnerable to climate change and stressful environments. We highlight the potential to tailor crops to a specific environment by utilising diversity inherent in an adapted landrace population. Tapping into natural biodiversity, while incorporating information about local environmental and climatic conditions, allows targeting of key traits and genotypes, enabling crop production in marginal soils. We outline future directions for the utilisation of genetic resources maintained in landrace collections to support sustainable agriculture through germplasm development via the use of genomics technologies and big data.
Collapse
Affiliation(s)
- Sidsel Birkelund Schmidt
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK; Innovation Centre for Organic Farming, Agro Food Park 26, 8200 Aarhus N., Denmark
| | - Lawrie K Brown
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - Allan Booth
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - John Wishart
- Agronomy Institute, Orkney College, University of the Highlands and Islands, Orkney, UK
| | - Pete E Hedley
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK
| | - Peter Martin
- Agronomy Institute, Orkney College, University of the Highlands and Islands, Orkney, UK
| | - Søren Husted
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Thorvaldsensvej 40, 1879 Frederiksberg C., Denmark
| | | | - Joanne Russell
- The James Hutton Institute, Invergowrie, Dundee DD2 5DA, UK.
| |
Collapse
|
6
|
Wang L, Xu J, Wang H, Chen T, You E, Bian H, Chen W, Zhang B, Shen Y. Population structure analysis and genome-wide association study of a hexaploid oat landrace and cultivar collection. FRONTIERS IN PLANT SCIENCE 2023; 14:1131751. [PMID: 37025134 PMCID: PMC10070682 DOI: 10.3389/fpls.2023.1131751] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 02/22/2023] [Indexed: 06/19/2023]
Abstract
INTRODUCTION Oat (Avena sativa L.) is an important cereal crop grown worldwide for grain and forage, owing to its high adaptability to diverse environments. However, the genetic and genomics research of oat is lagging behind that of other staple cereal crops. METHODS In this study, a collection of 288 oat lines originating worldwide was evaluated using 2,213 single nucleotide polymorphism (SNP) markers obtained from an oat iSelect 6K-beadchip array to study its genetic diversity, population structure, and linkage disequilibrium (LD) as well as the genotype-phenotype association for hullessness and lemma color. RESULTS The average gene diversity and polymorphic information content (PIC) were 0.324 and 0.262, respectively. The first three principal components (PCs) accounted for 30.33% of the genetic variation, indicating that the population structure of this panel of oat lines was stronger than that reported in most previous studies. In addition, accessions could be classified into two subpopulations using a Bayesian clustering approach, and the clustering pattern of accessions was closely associated with their region of origin. Additionally, evaluation of LD decay using 2,143 mapped markers revealed that the intrachromosomal whole-genome LD decayed rapidly to a critical r2 value of 0.156 for marker pairs separated by a genetic distance of 1.41 cM. Genome-wide association study (GWAS) detected six significant associations with the hullessness trait. Four of these six markers were located on the Mrg21 linkage group between 194.0 and 205.7 cM, while the other two significant markers mapped to Mrg05 and Mrg09. Three significant SNPs, showing strong association with lemma color, were located on linkage groups Mrg17, Mrg18, and Mrg20. DISCUSSION Our results discerned relevant patterns of genetic diversity, population structure, and LD among members of a worldwide collection of oat landraces and cultivars proposed to be 'typical' of the Qinghai-Tibetan Plateau. These results have important implications for further studies on association mapping and practical breeding in high-altitude oat.
Collapse
Affiliation(s)
- Lei Wang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Laboratory for Research and Utilization of Qinghai Tibetan Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Jinqing Xu
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Laboratory for Research and Utilization of Qinghai Tibetan Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Handong Wang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Laboratory for Research and Utilization of Qinghai Tibetan Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Tongrui Chen
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - En You
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Haiyan Bian
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
| | - Wenjie Chen
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Laboratory for Research and Utilization of Qinghai Tibetan Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Innovation Academy for Seed Design, Chinese Academy of Sciences, Xining, China
| | - Bo Zhang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Laboratory for Research and Utilization of Qinghai Tibetan Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Innovation Academy for Seed Design, Chinese Academy of Sciences, Xining, China
| | - Yuhu Shen
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Qinghai Provincial Key Laboratory of Crop Molecular Breeding, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Laboratory for Research and Utilization of Qinghai Tibetan Plateau Germplasm Resources, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China
- Innovation Academy for Seed Design, Chinese Academy of Sciences, Xining, China
| |
Collapse
|
7
|
Liu J, Dawe RK. Large haplotypes highlight a complex age structure within the maize pan-genome. Genome Res 2023; 33:359-370. [PMID: 36854668 PMCID: PMC10078284 DOI: 10.1101/gr.276705.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 02/21/2023] [Indexed: 03/02/2023]
Abstract
The genomes of maize and other eukaryotes contain stable haplotypes in regions of low recombination. These regions, including centromeres, long heterochromatic blocks, and rDNA arrays, have been difficult to analyze with respect to their diversity and origin. Greatly improved genome assemblies are now available that enable comparative genomics over these and other nongenic spaces. Using 26 complete maize genomes, we developed methods to align intergenic sequences while excluding genes and regulatory regions. The centromere haplotypes (cenhaps) extend for megabases on either side of the functional centromere regions and appear as evolutionary strata, with haplotype divergence/coalescence times dating as far back as 450 thousand years ago (kya). Application of the same methods to other low recombination regions (heterochromatic knobs and rDNA) and all intergenic spaces revealed that deep coalescence times are ubiquitous across the maize pan-genome. Divergence estimates vary over a broad timescale with peaks at ∼16 and 300 kya, reflecting a complex history of gene flow among diverging populations and changes in population size associated with domestication. Cenhaps and other long haplotypes provide vivid displays of this ancient diversity.
Collapse
Affiliation(s)
- Jianing Liu
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA
| | - R Kelly Dawe
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA;
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602, USA
| |
Collapse
|
8
|
Moreira LR, Klicka J, Smith BT. Demography and linked selection interact to shape the genomic landscape of codistributed woodpeckers during the Ice Age. Mol Ecol 2023; 32:1739-1759. [PMID: 36617622 DOI: 10.1111/mec.16841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 12/13/2022] [Accepted: 12/20/2022] [Indexed: 01/10/2023]
Abstract
The influence of genetic drift on population dynamics during Pleistocene glacial cycles is well understood, but the role of selection in shaping patterns of genomic variation during these events is less explored. We resequenced whole genomes to investigate how demography and natural selection interact to generate the genomic landscapes of Downy and Hairy Woodpecker, species codistributed in previously glaciated North America. First, we explored the spatial and temporal patterns of genomic diversity produced by neutral evolution. Next, we tested (i) whether levels of nucleotide diversity along the genome are correlated with intrinsic genomic properties, such as recombination rate and gene density, and (ii) whether different demographic trajectories impacted the efficacy of selection. Our results revealed cycles of bottleneck and expansion, and genetic structure associated with glacial refugia. Nucleotide diversity varied widely along the genome, but this variation was highly correlated between the species, suggesting the presence of conserved genomic features. In both taxa, nucleotide diversity was positively correlated with recombination rate and negatively correlated with gene density, suggesting that linked selection played a role in reducing diversity. Despite strong fluctuations in effective population size, the maintenance of relatively large populations during glaciations may have facilitated selection. Under these conditions, we found evidence that the individual demographic trajectory of populations modulated linked selection, with purifying selection being more efficient in removing deleterious alleles in large populations. These results highlight that while genome-wide variation reflects the expected signature of demographic change during climatic perturbations, the interaction of multiple processes produces a predictable and highly heterogeneous genomic landscape.
Collapse
Affiliation(s)
- Lucas R Moreira
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, New York, USA.,Department of Ornithology, American Museum of Natural History, New York City, New York, USA.,Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - John Klicka
- Burke Museum of Natural History and Culture and Department of Biology, University of Washington, Seattle, Washington, USA
| | - Brian Tilston Smith
- Department of Ornithology, American Museum of Natural History, New York City, New York, USA
| |
Collapse
|
9
|
Chen L, Luo J, Jin M, Yang N, Liu X, Peng Y, Li W, Phillips A, Cameron B, Bernal JS, Rellán-Álvarez R, Sawers RJH, Liu Q, Yin Y, Ye X, Yan J, Zhang Q, Zhang X, Wu S, Gui S, Wei W, Wang Y, Luo Y, Jiang C, Deng M, Jin M, Jian L, Yu Y, Zhang M, Yang X, Hufford MB, Fernie AR, Warburton ML, Ross-Ibarra J, Yan J. Genome sequencing reveals evidence of adaptive variation in the genus Zea. Nat Genet 2022; 54:1736-1745. [PMID: 36266506 DOI: 10.1038/s41588-022-01184-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 08/10/2022] [Indexed: 11/09/2022]
Abstract
Maize is a globally valuable commodity and one of the most extensively studied genetic model organisms. However, we know surprisingly little about the extent and potential utility of the genetic variation found in wild relatives of maize. Here, we characterize a high-density genomic variation map from 744 genomes encompassing maize and all wild taxa of the genus Zea, identifying over 70 million single-nucleotide polymorphisms. The variation map reveals evidence of selection within taxa displaying novel adaptations. We focus on adaptive alleles in highland teosinte and temperate maize, highlighting the key role of flowering-time-related pathways in their adaptation. To show the utility of variants in these data, we generate mutant alleles for two flowering-time candidate genes. This work provides an extensive sampling of the genetic diversity of Zea, resolving questions on evolution and identifying adaptive variants for direct use in modern breeding.
Collapse
Affiliation(s)
- Lu Chen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China.,State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Jingyun Luo
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Minliang Jin
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Ning Yang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China. .,Hubei Hongshan Laboratory, Wuhan, China.
| | - Xiangguo Liu
- Institute of Agricultural Biotechnology, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Yong Peng
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Wenqiang Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Alyssa Phillips
- Center for Population Biology, University of California Davis, Davis, CA, USA.,Department of Evolution and Ecology, University of California Davis, Davis, CA, USA
| | - Brenda Cameron
- Department of Evolution and Ecology, University of California Davis, Davis, CA, USA
| | - Julio S Bernal
- Department of Entomology, Texas A&M University, College Station, TX, USA
| | - Rubén Rellán-Álvarez
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, USA
| | - Ruairidh J H Sawers
- Department of Plant Science, The Pennsylvania State University, State College, PA, USA
| | - Qing Liu
- Institute of Agricultural Biotechnology, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Yuejia Yin
- Institute of Agricultural Biotechnology, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Xinnan Ye
- Institute of Agricultural Biotechnology, Jilin Academy of Agricultural Sciences, Changchun, China
| | - Jiali Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Qinghua Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Xiaoting Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Shenshen Wu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Songtao Gui
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Wenjie Wei
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Yuebin Wang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Yun Luo
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Chenglin Jiang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Min Deng
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Min Jin
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Liumei Jian
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Yanhui Yu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Maolin Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Xiaohong Yang
- National Maize Improvement Center of China, Beijing Key Laboratory of Crop Genetic Improvement, China Agricultural University, Beijing, China
| | - Matthew B Hufford
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA, USA
| | - Alisdair R Fernie
- Department of Molecular Physiology, Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, Germany
| | - Marilyn L Warburton
- United States Department of Agriculture-Agricultural Research Service: Western Regional Plant Introduction Station, Washington State University, Pullman, WA, USA
| | - Jeffrey Ross-Ibarra
- Department of Evolution and Ecology, Center for Population Biology, Genome Center, University of California Davis, Davis, CA, USA.
| | - Jianbing Yan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China. .,Hubei Hongshan Laboratory, Wuhan, China.
| |
Collapse
|
10
|
Booker TR, Payseur BA, Tigano A. Background selection under evolving recombination rates. Proc Biol Sci 2022; 289:20220782. [PMID: 35730151 PMCID: PMC9233929 DOI: 10.1098/rspb.2022.0782] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Background selection (BGS), the effect that purifying selection exerts on sites linked to deleterious alleles, is expected to be ubiquitous across eukaryotic genomes. The effects of BGS reflect the interplay of the rates and fitness effects of deleterious mutations with recombination. A fundamental assumption of BGS models is that recombination rates are invariant over time. However, in some lineages, recombination rates evolve rapidly, violating this central assumption. Here, we investigate how recombination rate evolution affects genetic variation under BGS. We show that recombination rate evolution modifies the effects of BGS in a manner similar to a localized change in the effective population size, potentially leading to underestimation or overestimation of the genome-wide effects of selection. Furthermore, we find evidence that recombination rate evolution in the ancestors of modern house mice may have impacted inferences of the genome-wide effects of selection in that species.
Collapse
Affiliation(s)
- Tom R. Booker
- Department of Zoology, University of British Columbia, Vancouver Campus, Vancouver, BC, Canada
| | - Bret A. Payseur
- Laboratory of Genetics, University of Wisconsin - Madison, Madison, WI, USA
| | - Anna Tigano
- Department of Biology, University of British Columbia, Okanagan Campus, Kelowna, BC, Canada
| |
Collapse
|
11
|
Fifer JE, Yasuda N, Yamakita T, Bove CB, Davies SW. Genetic divergence and range expansion in a western North Pacific coral. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152423. [PMID: 34942242 DOI: 10.1016/j.scitotenv.2021.152423] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 12/09/2021] [Accepted: 12/11/2021] [Indexed: 06/14/2023]
Abstract
Coral poleward range expansions have recently been observed in response to warming oceans. Range expansion can lead to reduced genetic diversity and increased frequency of deleterious mutations that were rare in core populations, potentially limiting the ability for adaptation and persistence in novel environments. Successful expansions that overcome these founder effects and colonize new habitat have been attributed to multiple introductions from different sources, hybridization with native populations, or rapid adaptive evolution. Here, we investigate population genomic patterns of the reef-building coral Acropora hyacinthus along a latitudinal cline that includes a well-established range expansion front in Japan using 2b-RAD sequencing. A total of 184 coral samples were collected across seven sites spanning from ~24°N to near its northern range front at ~33°N. We uncover the presence of three cryptic lineages of A. hyacinthus, which occupy discrete reefs within this region. Only one lineage is present along the expansion front and we find evidence for its historical occupation of marginal habitats. Within this lineage we also find evidence of bottleneck pressures associated with expansion events including higher clonality, increased linkage disequilibrium, and lower genetic diversity in range edge populations compared to core populations. Asymmetric migration between populations was also detected with lower migration from edge sites. Lastly, we describe genomic signatures of local adaptation potentially attributed to lower winter temperatures experienced at the more recently expanded northern populations. Together these data illuminate the genomic consequences of range expansion in a coral and highlight how adaptation to discrete environments along expansion fronts may facilitate further range expansion in this temperate coral lineage.
Collapse
Affiliation(s)
- James E Fifer
- Department of Biology, Boston University, Boston, MA 02215, USA.
| | - Nina Yasuda
- Department of Marine Biology and Environmental Sciences, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadainishi, Miyazaki 889-2192, Japan.
| | - Takehisa Yamakita
- Marine Biodiversity and Environmental Assessment Research Center, Japan Agency for Marine-Earth Science and Technology, 2-15 Natsushimacho, Yokosuka, Kanagawa 237-0061, Japan
| | - Colleen B Bove
- Department of Biology, Boston University, Boston, MA 02215, USA
| | - Sarah W Davies
- Department of Biology, Boston University, Boston, MA 02215, USA
| |
Collapse
|
12
|
Pettie N, Llopart A, Comeron JM. Meiotic, genomic and evolutionary properties of crossover distribution in Drosophila yakuba. PLoS Genet 2022; 18:e1010087. [PMID: 35320272 PMCID: PMC8979470 DOI: 10.1371/journal.pgen.1010087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 04/04/2022] [Accepted: 02/09/2022] [Indexed: 12/14/2022] Open
Abstract
The number and location of crossovers across genomes are highly regulated during meiosis, yet the key components controlling them are fast evolving, hindering our understanding of the mechanistic causes and evolutionary consequences of changes in crossover rates. Drosophila melanogaster has been a model species to study meiosis for more than a century, with an available high-resolution crossover map that is, nonetheless, missing for closely related species, thus preventing evolutionary context. Here, we applied a novel and highly efficient approach to generate whole-genome high-resolution crossover maps in D. yakuba to tackle multiple questions that benefit from being addressed collectively within an appropriate phylogenetic framework, in our case the D. melanogaster species subgroup. The genotyping of more than 1,600 individual meiotic events allowed us to identify several key distinct properties relative to D. melanogaster. We show that D. yakuba, in addition to higher crossover rates than D. melanogaster, has a stronger centromere effect and crossover assurance than any Drosophila species analyzed to date. We also report the presence of an active crossover-associated meiotic drive mechanism for the X chromosome that results in the preferential inclusion in oocytes of chromatids with crossovers. Our evolutionary and genomic analyses suggest that the genome-wide landscape of crossover rates in D. yakuba has been fairly stable and captures a significant signal of the ancestral crossover landscape for the whole D. melanogaster subgroup, even informative for the D. melanogaster lineage. Contemporary crossover rates in D. melanogaster, on the other hand, do not recapitulate ancestral crossovers landscapes. As a result, the temporal stability of crossover landscapes observed in D. yakuba makes this species an ideal system for applying population genetic models of selection and linkage, given that these models assume temporal constancy in linkage effects. Our studies emphasize the importance of generating multiple high-resolution crossover rate maps within a coherent phylogenetic context to broaden our understanding of crossover control during meiosis and to improve studies on the evolutionary consequences of variable crossover rates across genomes and time.
Collapse
Affiliation(s)
- Nikale Pettie
- Interdisciplinary Program in Genetics, University of Iowa, Iowa City, Iowa, United States of America
| | - Ana Llopart
- Interdisciplinary Program in Genetics, University of Iowa, Iowa City, Iowa, United States of America
- Department of Biology, University of Iowa, Iowa City, Iowa, United States of America
| | - Josep M. Comeron
- Interdisciplinary Program in Genetics, University of Iowa, Iowa City, Iowa, United States of America
- Department of Biology, University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
| |
Collapse
|
13
|
Samayoa LF, Olukolu BA, Yang CJ, Chen Q, Stetter MG, York AM, Sanchez-Gonzalez JDJ, Glaubitz JC, Bradbury PJ, Romay MC, Sun Q, Yang J, Ross-Ibarra J, Buckler ES, Doebley JF, Holland JB. Domestication reshaped the genetic basis of inbreeding depression in a maize landrace compared to its wild relative, teosinte. PLoS Genet 2021; 17:e1009797. [PMID: 34928949 PMCID: PMC8722731 DOI: 10.1371/journal.pgen.1009797] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 01/03/2022] [Accepted: 12/03/2021] [Indexed: 12/29/2022] Open
Abstract
Inbreeding depression is the reduction in fitness and vigor resulting from mating of close relatives observed in many plant and animal species. The extent to which the genetic load of mutations contributing to inbreeding depression is due to large-effect mutations versus variants with very small individual effects is unknown and may be affected by population history. We compared the effects of outcrossing and self-fertilization on 18 traits in a landrace population of maize, which underwent a population bottleneck during domestication, and a neighboring population of its wild relative teosinte. Inbreeding depression was greater in maize than teosinte for 15 of 18 traits, congruent with the greater segregating genetic load in the maize population that we predicted from sequence data. Parental breeding values were highly consistent between outcross and selfed offspring, indicating that additive effects determine most of the genetic value even in the presence of strong inbreeding depression. We developed a novel linkage scan to identify quantitative trait loci (QTL) representing large-effect rare variants carried by only a single parent, which were more important in teosinte than maize. Teosinte also carried more putative juvenile-acting lethal variants identified by segregation distortion. These results suggest a mixture of mostly polygenic, small-effect partially recessive effects in linkage disequilibrium underlying inbreeding depression, with an additional contribution from rare larger-effect variants that was more important in teosinte but depleted in maize following the domestication bottleneck. Purging associated with the maize domestication bottleneck may have selected against some large effect variants, but polygenic load is harder to purge and overall segregating mutational burden increased in maize compared to teosinte. Inbreeding depression is the reduction in fitness and vigor resulting from mating of close relatives observed in many plant and animal species. Mating of close relatives increases the probability that an individual inherits two non-functioning mutations at the same gene, resulting in lower fitness of such matings. We do not know the extent to which inbreeding depression is due to mutations with large-effects versus small-effect polygenic variants. We compared the effects of outcrossing and self-fertilization on 18 traits in a landrace population of maize, which underwent a population bottleneck during domestication, and a neighboring population of its wild relative teosinte. Inbreeding depression was greater in maize than teosinte for 15 of 18 traits and we found that this was consistent with higher predicted ‘genetic load’ in maize based solely on the evolutionary conservation of the sequence variants observed in the population. We also mapped genome positions associated with inbreeding depression, identifying more and larger-effect genetic variants in teosinte than maize. These results suggest that during domestication, some of the rare large-effect variants in teosinte were bred out, but many genetic variants of small effects on inbreeding depression increased in frequency maize.
Collapse
Affiliation(s)
- Luis Fernando Samayoa
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Bode A. Olukolu
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Chin Jian Yang
- Laboratory of Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Qiuyue Chen
- Laboratory of Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - Markus G. Stetter
- Institute for Plant Sciences and Center of Excellence on Plant Sciences, University of Cologne, Cologne, Germany
| | - Alessandra M. York
- Laboratory of Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | | | - Jeffrey C. Glaubitz
- Institute of Biotechnology, Cornell University, Ithaca, New York, United States of America
| | - Peter J. Bradbury
- US Department of Agriculture–Agricultural Research Service, Cornell University, Ithaca, New York, United States of America
| | - Maria Cinta Romay
- Institute of Biotechnology, Cornell University, Ithaca, New York, United States of America
| | - Qi Sun
- Institute of Biotechnology, Cornell University, Ithaca, New York, United States of America
| | - Jinliang Yang
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America
| | - Jeffrey Ross-Ibarra
- Department of Evolution and Ecology, Center for Population Biology, and Genome Center, University of California, Davis, California, United States of America
| | - Edward S. Buckler
- US Department of Agriculture–Agricultural Research Service, Cornell University, Ithaca, New York, United States of America
| | - John F. Doebley
- Laboratory of Genetics, University of Wisconsin–Madison, Madison, Wisconsin, United States of America
| | - James B. Holland
- Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina, United States of America
- United States Department of Agriculture–Agriculture Research Service, Raleigh, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
14
|
Burban E, Tenaillon MI, Le Rouzic A. Gene network simulations provide testable predictions for the molecular domestication syndrome. Genetics 2021; 220:6440055. [PMID: 34849852 DOI: 10.1093/genetics/iyab214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/15/2021] [Indexed: 11/14/2022] Open
Abstract
The domestication of plant species lead to repeatable morphological evolution, often referred to as the phenotypic domestication syndrome. Domestication is also associated with important genomic changes, such as the loss of genetic diversity compared to adequately large wild populations, and modifications of gene expression patterns. Here, we explored theoretically the effect of a domestication-like scenario on the evolution of gene regulatory networks. We ran population genetics simulations in which individuals were featured by their genotype (an interaction matrix encoding a gene regulatory network) and their gene expressions, representing the phenotypic level. Our domestication scenario included a population bottleneck and a selection switch mimicking human-mediated directional and canalizing selection, i.e., change in the optimal gene expression level and selection towards more stable expression across environments. We showed that domestication profoundly alters genetic architectures. Based on four examples of plant domestication scenarios, our simulations predict (i) a drop in neutral allelic diversity, (ii) a change in gene expression variance that depends upon the domestication scenario, (iii) transient maladaptive plasticity, (iv) a deep rewiring of the gene regulatory networks, with a trend towards gain of regulatory interactions, and (v) a global increase in the genetic correlations among gene expressions, with a loss of modularity in the resulting coexpression patterns and in the underlying networks. We provide empirically testable predictions on the differences of genetic architectures between wild and domesticated forms. The characterization of such systematic evolutionary changes in the genetic architecture of traits contributes to define a molecular domestication syndrome.
Collapse
Affiliation(s)
- Ewen Burban
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France.,CNRS, Univ. Rennes, ECOBIO-UMR 6553, F-35000 Rennes, France
| | - Maud I Tenaillon
- Université Paris-Saclay, INRAE, CNRS, AgroParisTech, GQE-Le Moulon, 91190, Gif-sur-Yvette, France
| | - Arnaud Le Rouzic
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France
| |
Collapse
|
15
|
Kumar R, Gyawali A, Morrison GD, Saski CA, Robertson DJ, Cook DD, Tharayil N, Schaefer RJ, Beissinger TM, Sekhon RS. Genetic Architecture of Maize Rind Strength Revealed by the Analysis of Divergently Selected Populations. PLANT & CELL PHYSIOLOGY 2021; 62:1199-1214. [PMID: 34015110 DOI: 10.1093/pcp/pcab059] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 05/04/2021] [Accepted: 05/19/2021] [Indexed: 06/12/2023]
Abstract
The strength of the stalk rind, measured as rind penetrometer resistance (RPR), is an important contributor to stalk lodging resistance. To enhance the genetic architecture of RPR, we combined selection mapping on populations developed by 15 cycles of divergent selection for high and low RPR with time-course transcriptomic and metabolic analyses of the stalks. Divergent selection significantly altered allele frequencies of 3,656 and 3,412 single- nucleotide polymorphisms (SNPs) in the high and low RPR populations, respectively. Surprisingly, only 110 (1.56%) SNPs under selection were common in both populations, while the majority (98.4%) were unique to each population. This result indicated that high and low RPR phenotypes are produced by biologically distinct mechanisms. Remarkably, regions harboring lignin and polysaccharide genes were preferentially selected in high and low RPR populations, respectively. The preferential selection was manifested as higher lignification and increased saccharification of the high and low RPR stalks, respectively. The evolution of distinct gene classes according to the direction of selection was unexpected in the context of parallel evolution and demonstrated that selection for a trait, albeit in different directions, does not necessarily act on the same genes. Tricin, a grass-specific monolignol that initiates the incorporation of lignin in the cell walls, emerged as a key determinant of RPR. Integration of selection mapping and transcriptomic analyses with published genetic studies of RPR identified several candidate genes including ZmMYB31, ZmNAC25, ZmMADS1, ZmEXPA2, ZmIAA41 and hk5. These findings provide a foundation for an enhanced understanding of RPR and the improvement of stalk lodging resistance.
Collapse
Affiliation(s)
- Rohit Kumar
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA
| | - Abiskar Gyawali
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211, USA
| | - Ginnie D Morrison
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, MO 65211, USA
| | - Christopher A Saski
- Department of Plant and Environmental Sciences, Clemson University, Clemson, SC 29634, USA
| | - Daniel J Robertson
- Department of Mechanical Engineering, University of Idaho, Moscow, ID, USA
| | - Douglas D Cook
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, USA
| | - Nishanth Tharayil
- Department of Plant and Environmental Sciences, Clemson University, Clemson, SC 29634, USA
| | | | - Timothy M Beissinger
- Department of Plant Breeding Methodology, University of Göttingen, Göttingen 37075, Germany
- Center for Integrated Breeding Research, University of Göttingen, Göttingen 37075, Germany
| | - Rajandeep S Sekhon
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA
| |
Collapse
|
16
|
Huang Y, Huang W, Meng Z, Braz GT, Li Y, Wang K, Wang H, Lai J, Jiang J, Dong Z, Jin W. Megabase-scale presence-absence variation with Tripsacum origin was under selection during maize domestication and adaptation. Genome Biol 2021; 22:237. [PMID: 34416918 PMCID: PMC8377971 DOI: 10.1186/s13059-021-02448-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 08/02/2021] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Structural variants (SVs) significantly drive genome diversity and environmental adaptation for diverse species. Unlike the prevalent small SVs (< kilobase-scale) in higher eukaryotes, large-size SVs rarely exist in the genome, but they function as one of the key evolutionary forces for speciation and adaptation. RESULTS In this study, we discover and characterize several megabase-scale presence-absence variations (PAVs) in the maize genome. Surprisingly, we identify a 3.2 Mb PAV fragment that shows high integrity and is present as complete presence or absence in the natural diversity panel. This PAV is embedded within the nucleolus organizer region (NOR), where the suppressed recombination is found to maintain the PAV against the evolutionary variation. Interestingly, by analyzing the sequence of this PAV, we not only reveal the domestication trace from teosinte to modern maize, but also the footprints of its origin from Tripsacum, shedding light on a previously unknown contribution from Tripsacum to the speciation of Zea species. The functional consequence of the Tripsacum segment migration is also investigated, and environmental fitness conferred by the PAV may explain the whole segment as a selection target during maize domestication and improvement. CONCLUSIONS These findings provide a novel perspective that Tripsacum contributes to Zea speciation, and also instantiate a strategy for evolutionary and functional analysis of the "fossil" structure variations during genome evolution and speciation.
Collapse
Affiliation(s)
- Yumin Huang
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China
| | - Wei Huang
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China
| | - Zhuang Meng
- Key Laboratory of Genetics, Breeding and Multiple Utilization of Corps (MOE), Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Guilherme Tomaz Braz
- Department of Plant Biology, Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA
| | - Yunfei Li
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China
| | - Kai Wang
- Key Laboratory of Genetics, Breeding and Multiple Utilization of Corps (MOE), Fujian Agriculture and Forestry University, Fuzhou, 350002, Fujian, China
| | - Hai Wang
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China
| | - Jinsheng Lai
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China
| | - Jiming Jiang
- Department of Plant Biology, Department of Horticulture, Michigan State University, East Lansing, MI, 48824, USA
| | - Zhaobin Dong
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China.
| | - Weiwei Jin
- State Key Laboratory of Plant Physiology and Biochemistry, National Maize Improvement Center, Key Laboratory of Crop Heterosis and Utilization (MOE), Joint International Research Laboratory of Crop Molecular Breeding (MOE), China Agricultural University, Beijing, 100193, China.
| |
Collapse
|
17
|
Hufford MB, Seetharam AS, Woodhouse MR, Chougule KM, Ou S, Liu J, Ricci WA, Guo T, Olson A, Qiu Y, Della Coletta R, Tittes S, Hudson AI, Marand AP, Wei S, Lu Z, Wang B, Tello-Ruiz MK, Piri RD, Wang N, Kim DW, Zeng Y, O'Connor CH, Li X, Gilbert AM, Baggs E, Krasileva KV, Portwood JL, Cannon EKS, Andorf CM, Manchanda N, Snodgrass SJ, Hufnagel DE, Jiang Q, Pedersen S, Syring ML, Kudrna DA, Llaca V, Fengler K, Schmitz RJ, Ross-Ibarra J, Yu J, Gent JI, Hirsch CN, Ware D, Dawe RK. De novo assembly, annotation, and comparative analysis of 26 diverse maize genomes. Science 2021; 373:655-662. [PMID: 34353948 PMCID: PMC8733867 DOI: 10.1126/science.abg5289] [Citation(s) in RCA: 233] [Impact Index Per Article: 77.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 06/24/2021] [Indexed: 12/24/2022]
Abstract
We report de novo genome assemblies, transcriptomes, annotations, and methylomes for the 26 inbreds that serve as the founders for the maize nested association mapping population. The number of pan-genes in these diverse genomes exceeds 103,000, with approximately a third found across all genotypes. The results demonstrate that the ancient tetraploid character of maize continues to degrade by fractionation to the present day. Excellent contiguity over repeat arrays and complete annotation of centromeres revealed additional variation in major cytological landmarks. We show that combining structural variation with single-nucleotide polymorphisms can improve the power of quantitative mapping studies. We also document variation at the level of DNA methylation and demonstrate that unmethylated regions are enriched for cis-regulatory elements that contribute to phenotypic variation.
Collapse
Affiliation(s)
- Matthew B Hufford
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Arun S Seetharam
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Genome Informatics Facility, Iowa State University, Ames, IA 50011, USA
| | - Margaret R Woodhouse
- USDA-ARS Corn Insects and Crop Genetics Research Unit, Iowa State University, Ames, IA 50011, USA
| | | | - Shujun Ou
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Jianing Liu
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - William A Ricci
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Tingting Guo
- Department of Agronomy, Iowa State University, Ames, IA 50011, USA
| | - Andrew Olson
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Yinjie Qiu
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
| | - Rafael Della Coletta
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
| | - Silas Tittes
- Center for Population Biology, University of California, Davis, CA 95616, USA
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | - Asher I Hudson
- Center for Population Biology, University of California, Davis, CA 95616, USA
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
| | | | - Sharon Wei
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Zhenyuan Lu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Bo Wang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | | | - Rebecca D Piri
- Institute of Bioinformatics, University of Georgia, Athens, GA 30602, USA
| | - Na Wang
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Dong Won Kim
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Yibing Zeng
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Christine H O'Connor
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN 55108, USA
| | - Xianran Li
- Department of Agronomy, Iowa State University, Ames, IA 50011, USA
| | - Amanda M Gilbert
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
| | - Erin Baggs
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Ksenia V Krasileva
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - John L Portwood
- USDA-ARS Corn Insects and Crop Genetics Research Unit, Iowa State University, Ames, IA 50011, USA
| | - Ethalinda K S Cannon
- USDA-ARS Corn Insects and Crop Genetics Research Unit, Iowa State University, Ames, IA 50011, USA
| | - Carson M Andorf
- USDA-ARS Corn Insects and Crop Genetics Research Unit, Iowa State University, Ames, IA 50011, USA
| | - Nancy Manchanda
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Samantha J Snodgrass
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - David E Hufnagel
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
- Virus and Prion Research Unit, National Animal Disease Center, USDA-ARS, Ames, IA, 50010, USA
| | - Qiuhan Jiang
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Sarah Pedersen
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - Michael L Syring
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA
| | - David A Kudrna
- Arizona Genomics Institute, School of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA
| | | | | | - Robert J Schmitz
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Jeffrey Ross-Ibarra
- Center for Population Biology, University of California, Davis, CA 95616, USA
- Department of Evolution and Ecology, University of California, Davis, CA 95616, USA
- Genome Center, University of California, Davis, CA 95616, USA
| | - Jianming Yu
- Department of Agronomy, Iowa State University, Ames, IA 50011, USA
| | - Jonathan I Gent
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Candice N Hirsch
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
| | - Doreen Ware
- USDA-ARS NAA Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, Ithaca, NY 14853, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - R Kelly Dawe
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, IA 50011, USA.
| |
Collapse
|
18
|
Blischak PD, Barker MS, Gutenkunst RN. Inferring the Demographic History of Inbred Species from Genome-Wide SNP Frequency Data. Mol Biol Evol 2021; 37:2124-2136. [PMID: 32068861 DOI: 10.1093/molbev/msaa042] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/04/2020] [Accepted: 02/13/2020] [Indexed: 01/04/2023] Open
Abstract
Demographic inference using the site frequency spectrum (SFS) is a common way to understand historical events affecting genetic variation. However, most methods for estimating demography from the SFS assume random mating within populations, precluding these types of analyses in inbred populations. To address this issue, we developed a model for the expected SFS that includes inbreeding by parameterizing individual genotypes using beta-binomial distributions. We then take the convolution of these genotype probabilities to calculate the expected frequency of biallelic variants in the population. Using simulations, we evaluated the model's ability to coestimate demography and inbreeding using one- and two-population models across a range of inbreeding levels. We also applied our method to two empirical examples, American pumas (Puma concolor) and domesticated cabbage (Brassica oleracea var. capitata), inferring models both with and without inbreeding to compare parameter estimates and model fit. Our simulations showed that we are able to accurately coestimate demographic parameters and inbreeding even for highly inbred populations (F = 0.9). In contrast, failing to include inbreeding generally resulted in inaccurate parameter estimates in simulated data and led to poor model fit in our empirical analyses. These results show that inbreeding can have a strong effect on demographic inference, a pattern that was especially noticeable for parameters involving changes in population size. Given the importance of these estimates for informing practices in conservation, agriculture, and elsewhere, our method provides an important advancement for accurately estimating the demographic histories of these species.
Collapse
Affiliation(s)
- Paul D Blischak
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ.,Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ
| | - Michael S Barker
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ
| | - Ryan N Gutenkunst
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ
| |
Collapse
|
19
|
Rifkin JL, Beaudry FEG, Humphries Z, Choudhury BI, Barrett SCH, Wright SI. Widespread Recombination Suppression Facilitates Plant Sex Chromosome Evolution. Mol Biol Evol 2021; 38:1018-1030. [PMID: 33095227 PMCID: PMC7947811 DOI: 10.1093/molbev/msaa271] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Classical models suggest that recombination rates on sex chromosomes evolve in a stepwise manner to localize sexually antagonistic variants in the sex in which they are beneficial, thereby lowering rates of recombination between X and Y chromosomes. However, it is also possible that sex chromosome formation occurs in regions with preexisting recombination suppression. To evaluate these possibilities, we constructed linkage maps and a chromosome-scale genome assembly for the dioecious plant Rumex hastatulus. This species has a polymorphic karyotype with a young neo-sex chromosome, resulting from a Robertsonian fusion between the X chromosome and an autosome, in part of its geographic range. We identified the shared and neo-sex chromosomes using comparative genetic maps of the two cytotypes. We found that sex-linked regions of both the ancestral and the neo-sex chromosomes are embedded in large regions of low recombination. Furthermore, our comparison of the recombination landscape of the neo-sex chromosome to its autosomal homolog indicates that low recombination rates mainly preceded sex linkage. These patterns are not unique to the sex chromosomes; all chromosomes were characterized by massive regions of suppressed recombination spanning most of each chromosome. This represents an extreme case of the periphery-biased recombination seen in other systems with large chromosomes. Across all chromosomes, gene and repetitive sequence density correlated with recombination rate, with patterns of variation differing by repetitive element type. Our findings suggest that ancestrally low rates of recombination may facilitate the formation and subsequent evolution of heteromorphic sex chromosomes.
Collapse
Affiliation(s)
- Joanna L Rifkin
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Felix E G Beaudry
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Zoë Humphries
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Baharul I Choudhury
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Spencer C H Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
| | - Stephen I Wright
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
- Centre for Analysis of Genome Evolution and Function, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
20
|
Trucchi E, Benazzo A, Lari M, Iob A, Vai S, Nanni L, Bellucci E, Bitocchi E, Raffini F, Xu C, Jackson SA, Lema V, Babot P, Oliszewski N, Gil A, Neme G, Michieli CT, De Lorenzi M, Calcagnile L, Caramelli D, Star B, de Boer H, Boessenkool S, Papa R, Bertorelle G. Ancient genomes reveal early Andean farmers selected common beans while preserving diversity. NATURE PLANTS 2021; 7:123-128. [PMID: 33558754 DOI: 10.1038/s41477-021-00848-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 01/04/2021] [Indexed: 05/10/2023]
Abstract
All crops are the product of a domestication process that started less than 12,000 years ago from one or more wild populations1,2. Farmers selected desirable phenotypic traits (such as improved energy accumulation, palatability of seeds and reduced natural shattering3) while leading domesticated populations through several more or less gradual demographic contractions2,4. As a consequence, the erosion of wild genetic variation5 is typical of modern cultivars, making them highly susceptible to pathogens, pests and environmental change6,7. The loss of genetic diversity hampers further crop improvement programmes to increase food production in a changing world, posing serious threats to food security8,9. Using both ancient and modern seeds, we analysed the temporal dynamics of genetic variation and selection during the domestication process of the common bean (Phaseolus vulgaris) in the southern Andes. Here, we show that most domestic traits were selected for before 2,500 years ago, with no or only minor loss of whole-genome heterozygosity. In fact, most of the changes at coding genes and linked regions that differentiate wild and domestic genomes are already present in the ancient genomes analysed here, and all ancient domestic genomes dated between 600 and 2,500 years ago are highly variable (at least as variable as modern genomes from the wild). Single seeds from modern cultivars show reduced variation when compared with ancient seeds, indicating that intensive selection within cultivars in the past few centuries probably partitioned ancestral variation within different genetically homogenous cultivars. When cultivars from different Andean regions are pooled, the genomic variation of the pool is higher than that observed in the pool of ancient seeds from north and central western Argentina. Considering that most desirable phenotypic traits are probably controlled by multiple polymorphic genes10, a plausible explanation of this decoupling of selection and genetic erosion is that early farmers applied a relatively weak selection pressure2 by using many phenotypically similar but genetically diverse individuals as parents. Our results imply that selection strategies during the past few centuries, as compared with earlier times, more intensively reduced genetic variation within cultivars and produced further improvements by focusing on a few plants carrying the traits of interest, at the cost of marked genetic erosion within Andean landraces.
Collapse
Affiliation(s)
- Emiliano Trucchi
- Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona, Italy.
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy.
| | - Andrea Benazzo
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Martina Lari
- Department of Biology, University of Florence, Firenze, Italy
| | - Alice Iob
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Stefania Vai
- Department of Biology, University of Florence, Firenze, Italy
| | - Laura Nanni
- Department of Agricultural, Food, and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Elisa Bellucci
- Department of Agricultural, Food, and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Elena Bitocchi
- Department of Agricultural, Food, and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Francesca Raffini
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Chunming Xu
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | - Scott A Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | - Verónica Lema
- Universidad Nacional de Córdoba, Córdoba, Argentina
- Conicet, Consejo Nacional de Investigaciones Científicas y Técnicas, Córdoba, Argentina
| | - Pilar Babot
- ISES, Instituto Superior de Estudios Sociales, CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Tucumán, Argentina
- Instituto de Arqueología y Museo, Universidad Nacional de Tucumán, Tucumán, Argentina
| | - Nurit Oliszewski
- ISES, Instituto Superior de Estudios Sociales, CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Tucumán, Argentina
- Universidad Nacional de Tucumán, Tucumán, Argentina
| | - Adolfo Gil
- Instituto de Evolución, Ecología Histórica y Ambiente (CONICET & UTN FRSR), San Rafael, Argentina
- Museo de Historia Natural de San Rafael, San Rafael, Argentina
| | - Gustavo Neme
- Instituto de Evolución, Ecología Histórica y Ambiente (CONICET & UTN FRSR), San Rafael, Argentina
- Museo de Historia Natural de San Rafael, San Rafael, Argentina
| | - Catalina Teresa Michieli
- Instituto de Investigaciones Arqueológicas y Museo "Prof. Mariano Gambier", Universidad Nacional de San Juan, San Juan, Argentina
| | | | - Lucio Calcagnile
- CEDAD (Centre of Applied Physics, Dating and Diagnostics), Department of Mathematics and Physics "Ennio De Giorgi", University of Salento, Lecce, Italy
| | - David Caramelli
- Department of Biology, University of Florence, Firenze, Italy
| | - Bastiaan Star
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Hugo de Boer
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Sanne Boessenkool
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Roberto Papa
- Department of Agricultural, Food, and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Giorgio Bertorelle
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy.
| |
Collapse
|
21
|
Lozano R, Gazave E, Dos Santos JPR, Stetter MG, Valluru R, Bandillo N, Fernandes SB, Brown PJ, Shakoor N, Mockler TC, Cooper EA, Taylor Perkins M, Buckler ES, Ross-Ibarra J, Gore MA. Comparative evolutionary genetics of deleterious load in sorghum and maize. NATURE PLANTS 2021; 7:17-24. [PMID: 33452486 DOI: 10.1038/s41477-020-00834-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 12/09/2020] [Indexed: 06/12/2023]
Abstract
Sorghum and maize share a close evolutionary history that can be explored through comparative genomics1,2. To perform a large-scale comparison of the genomic variation between these two species, we analysed ~13 million variants identified from whole-genome resequencing of 499 sorghum lines together with 25 million variants previously identified in 1,218 maize lines. Deleterious mutations in both species were prevalent in pericentromeric regions, enriched in non-syntenic genes and present at low allele frequencies. A comparison of deleterious burden between sorghum and maize revealed that sorghum, in contrast to maize, departed from the domestication-cost hypothesis that predicts a higher deleterious burden among domesticates compared with wild lines. Additionally, sorghum and maize population genetic summary statistics were used to predict a gene deleterious index with an accuracy greater than 0.5. This research represents a key step towards understanding the evolutionary dynamics of deleterious variants in sorghum and provides a comparative genomics framework to start prioritizing these variants for removal through genome editing and breeding.
Collapse
Affiliation(s)
- Roberto Lozano
- Plant Breeding and Genetics, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - Elodie Gazave
- Plant Breeding and Genetics, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
- Institute of Biotechnology, Cornell University, Ithaca, NY, USA
| | - Jhonathan P R Dos Santos
- Plant Breeding and Genetics, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
- Department of Genetics, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, Brazil
| | - Markus G Stetter
- Botanical Institute, Biozentrum, University of Cologne, Cologne, Germany
| | - Ravi Valluru
- Institute for Genomic Diversity, Cornell University, Ithaca, NY, USA
- University of Lincoln, Lincoln, UK
| | - Nonoy Bandillo
- Institute for Genomic Diversity, Cornell University, Ithaca, NY, USA
- Department of Plant Sciences, North Dakota State University, Fargo, ND, USA
| | - Samuel B Fernandes
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Patrick J Brown
- Department of Plant Sciences, University of California Davis, Davis, CA, USA
| | - Nadia Shakoor
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Todd C Mockler
- Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Elizabeth A Cooper
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC, USA
| | - M Taylor Perkins
- Department of Evolution and Ecology, University of California Davis, Davis, CA, USA
| | - Edward S Buckler
- Plant Breeding and Genetics, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
- Institute for Genomic Diversity, Cornell University, Ithaca, NY, USA
- United States Department of Agriculture, Agricultural Research Service (USDA-ARS) R. W. Holley Center for Agriculture and Health, Ithaca, NY, USA
| | - Jeffrey Ross-Ibarra
- Department of Evolution and Ecology, University of California Davis, Davis, CA, USA.
- Center for Population Biology and Genome Center, University of California Davis, Davis, CA, USA.
| | - Michael A Gore
- Plant Breeding and Genetics, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA.
| |
Collapse
|
22
|
Yan H, Zhou P, Peng Y, Bekele WA, Ren C, Tinker NA, Peng Y. Genetic diversity and genome-wide association analysis in Chinese hulless oat germplasm. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:3365-3380. [PMID: 32888041 DOI: 10.1007/s00122-020-03674-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 08/21/2020] [Indexed: 05/12/2023]
Abstract
Genotyping-by-sequencing (GBS)-derived molecular markers reveal the distinct genetic population structure and relatively narrow genetic diversity of Chinese hulless oat landraces. Four markers linked to the naked grain gene (N1) are identified by genome-wide association study (GWAS). Interest in hulless oat (Avena sativa ssp. nuda), a variant of common oat (A. sativa) domesticated in Western Asia, has increased in recent years due to its free-threshing attribute and its domestication history. However, the genetic diversity and population structure of hulless oat, as well as the genetic mechanism of hullessness, are poorly understood. In this study, the genetic diversity and population structure of a worldwide sample of 805 oat lines including 186 hulless oats were investigated using genotyping-by-sequencing. Population structure analyses showed a strong genetic differentiation between hulless landraces vs other oat lines, including the modern hulless cultivars. The distinct subpopulation stratification of hulless landraces and their low genetic diversity suggests that a domestication bottleneck existed in hulless landraces. Additionally, low genetic diversity within European oats and strong differentiation between the spring oats and southern origin oat lines revealed by previous studies were also observed in this study. Genomic regions contributing to these genetic differentiations suggest that genetic loci related to growth habit and stress resistance may have been under intense selection, rather than the hulless-related genomic regions. Genome-wide association analysis detected four markers that were highly associated with hullessness. Three of these were mapped on linkage group Mrg21 at a genetic position between 195.7 and 212.1 cM, providing robust evidence that the dominant N1 locus located on Mrg21 is the single major factor controlling this trait.
Collapse
Affiliation(s)
- Honghai Yan
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Pingping Zhou
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Yun Peng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, China
| | - Wubishet A Bekele
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Ave, Ottawa, ON, K1A0C6, Canada
| | - Changzhong Ren
- Baicheng Academy of Agricultural Sciences, Baicheng, 137000, China
| | - Nicholas A Tinker
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, 960 Carling Ave, Ottawa, ON, K1A0C6, Canada.
| | - Yuanying Peng
- Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, China.
| |
Collapse
|
23
|
Arnoux S, Fraïsse C, Sauvage C. Genomic inference of complex domestication histories in three Solanaceae species. J Evol Biol 2020; 34:270-283. [PMID: 33107098 DOI: 10.1111/jeb.13723] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 10/15/2020] [Indexed: 12/30/2022]
Abstract
Domestication is a human-induced selection process that imprints the genomes of domesticated populations over a short evolutionary time scale and that occurs in a given demographic context. Reconstructing historical gene flow, effective population size changes and their timing is therefore of fundamental interest to understand how plant demography and human selection jointly shape genomic divergence during domestication. Yet, the comparison under a single statistical framework of independent domestication histories across different crop species has been little evaluated so far. Thus, it is unclear whether domestication leads to convergent demographic changes that similarly affect crop genomes. To address this question, we used existing and new transcriptome data on three crop species of Solanaceae (eggplant, pepper and tomato), together with their close wild relatives. We fitted twelve demographic models of increasing complexity on the unfolded joint allele frequency spectrum for each wild/crop pair, and we found evidence for both shared and species-specific demographic processes between species. A convergent history of domestication with gene flow was inferred for all three species, along with evidence of strong reduction in the effective population size during the cultivation stage of tomato and pepper. The absence of any reduction in size of the crop in eggplant stands out from the classical view of the domestication process; as does the existence of a "protracted period" of management before cultivation. Our results also suggest divergent management strategies of modern cultivars among species as their current demography substantially differs. Finally, the timing of domestication is species-specific and supported by the few historical records available.
Collapse
Affiliation(s)
- Stéphanie Arnoux
- INRA UR1052 GAFL, Centre de Recherche INRA PACA, Avignon Cedex 9, France.,Vilmorin SA, Lédenon, France
| | | | - Christopher Sauvage
- INRA UR1052 GAFL, Centre de Recherche INRA PACA, Avignon Cedex 9, France.,Syngenta SAS France, Saint Sauveur, France
| |
Collapse
|
24
|
Xu G, Lyu J, Li Q, Liu H, Wang D, Zhang M, Springer NM, Ross-Ibarra J, Yang J. Evolutionary and functional genomics of DNA methylation in maize domestication and improvement. Nat Commun 2020; 11:5539. [PMID: 33139747 PMCID: PMC7606521 DOI: 10.1038/s41467-020-19333-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 10/08/2020] [Indexed: 12/23/2022] Open
Abstract
DNA methylation is a ubiquitous chromatin feature, present in 25% of cytosines in the maize genome, but variation and evolution of the methylation landscape during maize domestication remain largely unknown. Here, we leverage whole-genome sequencing (WGS) and whole-genome bisulfite sequencing (WGBS) data on populations of modern maize, landrace, and teosinte (Zea mays ssp. parviglumis) to estimate epimutation rates and selection coefficients. We find weak evidence for direct selection on DNA methylation in any context, but thousands of differentially methylated regions (DMRs) are identified population-wide that are correlated with recent selection. For two trait-associated DMRs, vgt1-DMR and tb1-DMR, HiChIP data indicate that the interactive loops between DMRs and respective downstream genes are present in B73, a modern maize line, but absent in teosinte. Our results enable a better understanding of the evolutionary forces acting on patterns of DNA methylation and suggest a role of methylation variation in adaptive evolution. Variation and evolution of DNA methylation during maize domestication remain largely unknown. Here, the authors generate genome and methylome sequencing data as well as HiChIP-based interactome data to investigate the adaptive and phenotypic consequences of methylation variations in maize.
Collapse
Affiliation(s)
- Gen Xu
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.,Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Jing Lyu
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.,Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Qing Li
- Department of Plant Biology, Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN, 55108, USA.,National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, 430070, China
| | - Han Liu
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - Dafang Wang
- Division of Math and Sciences, Delta State University, Cleveland, MS, 38733, USA
| | - Mei Zhang
- Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Nanxincun 20, Fragrant Hill, Beijing, 100093, China
| | - Nathan M Springer
- Department of Plant Biology, Microbial and Plant Genomics Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Jeffrey Ross-Ibarra
- Department of Evolution and Ecology, Center for Population Biology and Genome Center, University of California, Davis, CA, 95616, USA
| | - Jinliang Yang
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA. .,Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.
| |
Collapse
|
25
|
Feng S, Liu Z, Hu Y, Tian J, Yang T, Wei A. Genomic analysis reveals the genetic diversity, population structure, evolutionary history and relationships of Chinese pepper. HORTICULTURE RESEARCH 2020; 7:158. [PMID: 33082965 PMCID: PMC7527552 DOI: 10.1038/s41438-020-00376-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 07/07/2020] [Accepted: 07/13/2020] [Indexed: 05/26/2023]
Abstract
Chinese pepper, mainly including Zanthoxylum bungeanum and Zanthoxylum armatum, is an economically important crop popular in Asian countries due to its unique taste characteristics and potential medical uses. Numerous cultivars of Chinese pepper have been developed in China through long-term domestication. To better understand the population structure, demographic history, and speciation of Chinese pepper, we performed a comprehensive analysis at a genome-wide level by analyzing 38,395 genomic SNPs that were identified in 112 cultivated and wild accessions using a high-throughput genome-wide genotyping-by-sequencing (GBS) approach. Our analysis provides genetic evidence of multiple splitting events occurring between and within species, resulting in at least four clades in Z. bungeanum and two clades in Z. armatum. Despite no evidence of recent admixture between species, we detected substantial gene flow within species. Estimates of demographic dynamics and species distribution modeling suggest that climatic oscillations during the Pleistocene (including the Penultimate Glaciation and the Last Glacial Maximum) and recent domestication events together shaped the demography and evolution of Chinese pepper. Our analyses also suggest that southeastern Gansu province is the most likely origin of Z. bungeanum in China. These findings provide comprehensive insights into genetic diversity, population structure, demography, and adaptation in Zanthoxylum.
Collapse
Affiliation(s)
- Shijing Feng
- College of Forestry, Northwest A&F University, Yangling, 712100 Shaanxi China
- College of Life Science, Northwest A&F University, Yangling, 712100 Shaanxi China
- Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Yangling, 712100 Shaanxi China
| | - Zhenshan Liu
- College of Life Science, Northwest A&F University, Yangling, 712100 Shaanxi China
| | - Yang Hu
- College of Forestry, Northwest A&F University, Yangling, 712100 Shaanxi China
- Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Yangling, 712100 Shaanxi China
| | - Jieyun Tian
- College of Forestry, Northwest A&F University, Yangling, 712100 Shaanxi China
- Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Yangling, 712100 Shaanxi China
| | - Tuxi Yang
- College of Forestry, Northwest A&F University, Yangling, 712100 Shaanxi China
- Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Yangling, 712100 Shaanxi China
| | - Anzhi Wei
- College of Forestry, Northwest A&F University, Yangling, 712100 Shaanxi China
- Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration, Yangling, 712100 Shaanxi China
| |
Collapse
|
26
|
Buffalo V, Coop G. Estimating the genome-wide contribution of selection to temporal allele frequency change. Proc Natl Acad Sci U S A 2020; 117:20672-20680. [PMID: 32817464 PMCID: PMC7456072 DOI: 10.1073/pnas.1919039117] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Rapid phenotypic adaptation is often observed in natural populations and selection experiments. However, detecting the genome-wide impact of this selection is difficult since adaptation often proceeds from standing variation and selection on polygenic traits, both of which may leave faint genomic signals indistinguishable from a noisy background of genetic drift. One promising signal comes from the genome-wide covariance between allele frequency changes observable from temporal genomic data (e.g., evolve-and-resequence studies). These temporal covariances reflect how heritable fitness variation in the population leads changes in allele frequencies at one time point to be predictive of the changes at later time points, as alleles are indirectly selected due to remaining associations with selected alleles. Since genetic drift does not lead to temporal covariance, we can use these covariances to estimate what fraction of the variation in allele frequency change through time is driven by linked selection. Here, we reanalyze three selection experiments to quantify the effects of linked selection over short timescales using covariance among time points and across replicates. We estimate that at least 17 to 37% of allele frequency change is driven by selection in these experiments. Against this background of positive genome-wide temporal covariances, we also identify signals of negative temporal covariance corresponding to reversals in the direction of selection for a reasonable proportion of loci over the time course of a selection experiment. Overall, we find that in the three studies we analyzed, linked selection has a large impact on short-term allele frequency dynamics that is readily distinguishable from genetic drift.
Collapse
Affiliation(s)
- Vince Buffalo
- Population Biology Graduate Group, University of California, Davis, CA 95616;
- Center for Population Biology, Department of Evolution and Ecology, University of California, Davis, CA 95616
| | - Graham Coop
- Center for Population Biology, Department of Evolution and Ecology, University of California, Davis, CA 95616
| |
Collapse
|
27
|
Ramstein GP, Larsson SJ, Cook JP, Edwards JW, Ersoz ES, Flint-Garcia S, Gardner CA, Holland JB, Lorenz AJ, McMullen MD, Millard MJ, Rocheford TR, Tuinstra MR, Bradbury PJ, Buckler ES, Romay MC. Dominance Effects and Functional Enrichments Improve Prediction of Agronomic Traits in Hybrid Maize. Genetics 2020; 215:215-230. [PMID: 32152047 PMCID: PMC7198274 DOI: 10.1534/genetics.120.303025] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 02/26/2020] [Indexed: 01/04/2023] Open
Abstract
Single-cross hybrids have been critical to the improvement of maize (Zea mays L.), but the characterization of their genetic architectures remains challenging. Previous studies of hybrid maize have shown the contribution of within-locus complementation effects (dominance) and their differential importance across functional classes of loci. However, they have generally considered panels of limited genetic diversity, and have shown little benefit from genomic prediction based on dominance or functional enrichments. This study investigates the relevance of dominance and functional classes of variants in genomic models for agronomic traits in diverse populations of hybrid maize. We based our analyses on a diverse panel of inbred lines crossed with two testers representative of the major heterotic groups in the U.S. (1106 hybrids), as well as a collection of 24 biparental populations crossed with a single tester (1640 hybrids). We investigated three agronomic traits: days to silking (DTS), plant height (PH), and grain yield (GY). Our results point to the presence of dominance for all traits, but also among-locus complementation (epistasis) for DTS and genotype-by-environment interactions for GY. Consistently, dominance improved genomic prediction for PH only. In addition, we assessed enrichment of genetic effects in classes defined by genic regions (gene annotation), structural features (recombination rate and chromatin openness), and evolutionary features (minor allele frequency and evolutionary constraint). We found support for enrichment in genic regions and subsequent improvement of genomic prediction for all traits. Our results suggest that dominance and gene annotations improve genomic prediction across diverse populations in hybrid maize.
Collapse
Affiliation(s)
| | - Sara J Larsson
- Section of Plant Breeding and Genetics, Cornell University, Ithaca, New York 14853
| | - Jason P Cook
- Division of Plant Science, University of Missouri, Columbia, Missouri 56211
| | - Jode W Edwards
- U.S. Department of Agriculture-Agricultural Research Service, Ames, Iowa 50011
| | | | - Sherry Flint-Garcia
- U.S. Department of Agriculture-Agricultural Research Service, University of Missouri, Columbia, Missouri 56211
| | - Candice A Gardner
- U.S. Department of Agriculture-Agricultural Research Service, Ames, Iowa 50011
| | - James B Holland
- U.S. Department of Agriculture-Agricultural Research Service, Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695
| | - Aaron J Lorenz
- Department of Agronomy and Horticulture, University of Nebraska, Lincoln, Nebraska 68588
| | - Michael D McMullen
- U.S. Department of Agriculture-Agricultural Research Service, University of Missouri, Columbia, Missouri 56211
| | - Mark J Millard
- U.S. Department of Agriculture-Agricultural Research Service, Ames, Iowa 50011
| | | | | | - Peter J Bradbury
- U.S. Department of Agriculture-Agricultural Research Service, Ithaca, New York 14853
| | - Edward S Buckler
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853
- U.S. Department of Agriculture-Agricultural Research Service, Ithaca, New York 14853
| | - M Cinta Romay
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853
| |
Collapse
|
28
|
Turner-Hissong SD, Mabry ME, Beissinger TM, Ross-Ibarra J, Pires JC. Evolutionary insights into plant breeding. CURRENT OPINION IN PLANT BIOLOGY 2020; 54:93-100. [PMID: 32325397 DOI: 10.1016/j.pbi.2020.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 01/20/2020] [Accepted: 03/04/2020] [Indexed: 06/11/2023]
Abstract
Crop domestication is a fascinating area of study, as shown by a multitude of recent reviews. Coupled with the increasing availability of genomic and phenomic resources in numerous crop species, insights from evolutionary biology will enable a deeper understanding of the genetic architecture and short-term evolution of complex traits, which can be used to inform selection strategies. Future advances in crop improvement will rely on the integration of population genetics with plant breeding methodology, and the development of community resources to support research in a variety of crop life histories and reproductive strategies. We highlight recent advances related to the role of selective sweeps and demographic history in shaping genetic architecture, how these breakthroughs can inform selection strategies, and the application of precision gene editing to leverage these connections.
Collapse
Affiliation(s)
- Sarah D Turner-Hissong
- Center for Population Biology, University of California, Davis, CA, USA; Department of Evolution and Ecology, University of California, Davis, CA, USA.
| | - Makenzie E Mabry
- Bond Life Science Center and Division of Biological Sciences, University of Missouri, Columbia, MO, USA
| | - Timothy M Beissinger
- Division of Plant Breeding Methodology, Department of Crop Science, Georg-August-Universtät, Göttingen, Germany; Center for Integrated Breeding Research, Georg-August-Universtät, Göttingen, Germany
| | - Jeffrey Ross-Ibarra
- Center for Population Biology, University of California, Davis, CA, USA; Department of Evolution and Ecology, University of California, Davis, CA, USA
| | - J Chris Pires
- Bond Life Science Center and Division of Biological Sciences, University of Missouri, Columbia, MO, USA
| |
Collapse
|
29
|
Kartje ME, Jing P, Payseur BA. Weak Correlation between Nucleotide Variation and Recombination Rate across the House Mouse Genome. Genome Biol Evol 2020; 12:293-299. [PMID: 32108880 PMCID: PMC7186785 DOI: 10.1093/gbe/evaa045] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2020] [Indexed: 01/01/2023] Open
Abstract
Positive selection and purifying selection reduce levels of variation at linked neutral loci. One consequence of these processes is that the amount of neutral diversity and the meiotic recombination rate are predicted to be positively correlated across the genome-a prediction met in some species but not others. To better document the prevalence of selection at linked sites, we used new and published whole-genome sequences to survey nucleotide variation in population samples of the western European house mouse (Mus musculus domesticus) from Germany, France, and Gough Island, a remote volcanic island in the south Atlantic. Correlations between sequence variation and recombination rates estimated independently from dense linkage maps were consistently very weak (ρ ≤ 0.06), though they exceeded conventional significance thresholds. This pattern persisted in comparisons between genomic regions with the highest and lowest recombination rates, as well as in models incorporating the density of transcribed sites, the density of CpG dinucleotides, and divergence between mouse and rat as covariates. We conclude that natural selection affects linked neutral variation in a restricted manner in the western European house mouse.
Collapse
Affiliation(s)
- Michael E Kartje
- Laboratory of Genetics, University of Wisconsin – Madison, Madison
| | - Peicheng Jing
- Laboratory of Genetics, University of Wisconsin – Madison, Madison
| | - Bret A Payseur
- Laboratory of Genetics, University of Wisconsin – Madison, Madison
| |
Collapse
|
30
|
Park B, Burke JM. Phylogeography and the Evolutionary History of Sunflower ( Helianthus annuus L.): Wild Diversity and the Dynamics of Domestication. Genes (Basel) 2020; 11:E266. [PMID: 32121324 PMCID: PMC7140811 DOI: 10.3390/genes11030266] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/21/2020] [Accepted: 02/27/2020] [Indexed: 12/04/2022] Open
Abstract
Patterns of genetic variation in crops are the result of selection and demographic changes that occurred during their domestication and improvement. In many cases, we have an incomplete picture of the origin of crops in the context of their wild progenitors, particularly with regard to the processes producing observed levels of standing genetic variation. Here, we analyzed sequence diversity in cultivated sunflower (Helianthus annuus L.) and its wild progenitor (common sunflower, also H. annuus) to reconstruct phylogeographic relationships and population genetic/demographic patterns across sunflower. In common sunflower, south-north patterns in the distribution of nucleotide diversity and lineage splitting indicate a history of rapid postglacial range expansion from southern refugia. Cultivated sunflower accessions formed a clade, nested among wild populations from the Great Plains, confirming a single domestication event in central North America. Furthermore, cultivated accessions sorted by market type (i.e., oilseed vs. confectionery) rather than breeding pool, recapitulating the secondary development of oil-rich cultivars during its breeding history. Across sunflower, estimates of nucleotide diversity and effective population sizes suggest that cultivated sunflower underwent significant population bottlenecks following its establishment ~5000 years ago. The patterns inferred here corroborate those from previous studies of sunflower domestication, and provide a comprehensive overview of its evolutionary history.
Collapse
Affiliation(s)
- Brian Park
- Department of Plant Biology, University of Georgia, Miller Plant Sciences Bldg., Athens, GA 30602, USA;
| | | |
Collapse
|
31
|
The Temporal Dynamics of Background Selection in Nonequilibrium Populations. Genetics 2020; 214:1019-1030. [PMID: 32071195 DOI: 10.1534/genetics.119.302892] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Accepted: 01/30/2020] [Indexed: 01/06/2023] Open
Abstract
Neutral genetic diversity across the genome is determined by the complex interplay of mutation, demographic history, and natural selection. While the direct action of natural selection is limited to functional loci across the genome, its impact can have effects on nearby neutral loci due to genetic linkage. These effects of selection at linked sites, referred to as genetic hitchhiking and background selection (BGS), are pervasive across natural populations. However, only recently has there been a focus on the joint consequences of demography and selection at linked sites, and some empirical studies have come to apparently contradictory conclusions as to their combined effects. To understand the relationship between demography and selection at linked sites, we conducted an extensive forward simulation study of BGS under a range of demographic models. We found that the relative levels of diversity in BGS and neutral regions vary over time and that the initial dynamics after a population size change are often in the opposite direction of the long-term expected trajectory. Our detailed observations of the temporal dynamics of neutral diversity in the context of selection at linked sites in nonequilibrium populations provide new intuition about why patterns of diversity under BGS vary through time in natural populations and help reconcile previously contradictory observations. Most notably, our results highlight that classical models of BGS are poorly suited for predicting diversity in nonequilibrium populations.
Collapse
|
32
|
Pyhäjärvi T, Kujala ST, Savolainen O. 275 years of forestry meets genomics in Pinus sylvestris. Evol Appl 2020; 13:11-30. [PMID: 31988655 PMCID: PMC6966708 DOI: 10.1111/eva.12809] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 04/05/2019] [Accepted: 04/24/2019] [Indexed: 12/12/2022] Open
Abstract
Pinus sylvestris has a long history of basic and applied research that is relevant for both forestry and evolutionary studies. Its patterns of adaptive variation and role in forest economic and ecological systems have been studied extensively for nearly 275 years, detailed demography for a 100 years and mating system more than 50 years. However, its reference genome sequence is not yet available and genomic studies have been lagging compared to, for example, Pinus taeda and Picea abies, two other economically important conifers. Despite the lack of reference genome, many modern genomic methods are applicable for a more detailed look at its biological characteristics. For example, RNA-seq has revealed a complex transcriptional landscape and targeted DNA sequencing displays an excess of rare variants and geographically homogenously distributed molecular genetic diversity. Current DNA and RNA resources can be used as a reference for gene expression studies, SNP discovery, and further targeted sequencing. In the future, specific consequences of the large genome size, such as functional effects of regulatory open chromatin regions and transposable elements, should be investigated more carefully. For forest breeding and long-term management purposes, genomic data can help in assessing the genetic basis of inbreeding depression and the application of genomic tools for genomic prediction and relatedness estimates. Given the challenges of breeding (long generation time, no easy vegetative propagation) and the economic importance, application of genomic tools has a potential to have a considerable impact. Here, we explore how genomic characteristics of P. sylvestris, such as rare alleles and the low extent of linkage disequilibrium, impact the applicability and power of the tools.
Collapse
Affiliation(s)
- Tanja Pyhäjärvi
- Department of Ecology and GeneticsUniversity of OuluOuluFinland
- Biocenter OuluUniversity of OuluOuluFinland
| | | | - Outi Savolainen
- Department of Ecology and GeneticsUniversity of OuluOuluFinland
- Biocenter OuluUniversity of OuluOuluFinland
| |
Collapse
|
33
|
Abstract
The Multiple Sequentially Markovian Coalescent (MSMC) is a population genetic method and software for inferring demographic history and population structure through time from genome sequences. Here we describe the main program MSMC and its successor MSMC2. We go through all the necessary steps of processing genomic data from BAM files all the way to generating plots of inferred population size and separation histories. Some background on the methodology itself is provided, as well as bash scripts and python source code to run the necessary programs. The reader is also referred to community resources such as a mailing list and github repositories for further advice.
Collapse
Affiliation(s)
- Stephan Schiffels
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany.
| | - Ke Wang
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Jena, Germany
| |
Collapse
|
34
|
Abstract
Maize is an excellent model for the study of plant adaptation. Indeed, post domestication maize quickly adapted to a host of new environments across the globe. And work over the last decade has begun to highlight the role of the wild relatives of maize-the teosintes Zea mays ssp. parviglumis and ssp. mexicana-as excellent models for dissecting long-term local adaptation.Although human-driven selection associated with maize domestication has been extensively studied, the genetic basis of natural variation is still poorly understood. Here we review studies on the genetic basis of adaptation and plasticity in maize and its wild relatives. We highlight a range of different processes that contribute to adaptation and discuss evidence from natural, cultivated, and experimental populations. From an applied perspective, understanding the genetic bases of adaptation and the contribution of plasticity will provide us with new tools to both better understand and mitigate the effect of climate changes on natural and cultivated populations.
Collapse
|
35
|
Stetter MG, Vidal-Villarejo M, Schmid KJ. Parallel Seed Color Adaptation during Multiple Domestication Attempts of an Ancient New World Grain. Mol Biol Evol 2019; 37:1407-1419. [DOI: 10.1093/molbev/msz304] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AbstractThousands of plants have been selected as crops; yet, only a few are fully domesticated. The lack of adaptation to agroecological environments of many crop plants with few characteristic domestication traits potentially has genetic causes. Here, we investigate the incomplete domestication of an ancient grain from the Americas, amaranth. Although three grain amaranth species have been cultivated as crop for millennia, all three lack key domestication traits. We sequenced 121 crop and wild individuals to investigate the genomic signature of repeated incomplete adaptation. Our analysis shows that grain amaranth has been domesticated three times from a single wild ancestor. One trait that has been selected during domestication in all three grain species is the seed color, which changed from dark seeds to white seeds. We were able to map the genetic control of the seed color adaptation to two genomic regions on chromosomes 3 and 9, employing three independent mapping populations. Within the locus on chromosome 9, we identify an MYB-like transcription factor gene, a known regulator for seed color variation in other plant species. We identify a soft selective sweep in this genomic region in one of the crop species but not in the other two species. The demographic analysis of wild and domesticated amaranths revealed a population bottleneck predating the domestication of grain amaranth. Our results indicate that a reduced level of ancestral genetic variation did not prevent the selection of traits with a simple genetic architecture but may have limited the adaptation of complex domestication traits.
Collapse
Affiliation(s)
- Markus G Stetter
- Botanical Institute, University of Cologne, Cologne, Germany
- Department of Plant Breeding, Population Genetics and Seed Science, University of Hohenheim, Stuttgart, Germany
| | - Mireia Vidal-Villarejo
- Department of Plant Breeding, Population Genetics and Seed Science, University of Hohenheim, Stuttgart, Germany
| | - Karl J Schmid
- Department of Plant Breeding, Population Genetics and Seed Science, University of Hohenheim, Stuttgart, Germany
| |
Collapse
|
36
|
Buffalo V, Coop G. The Linked Selection Signature of Rapid Adaptation in Temporal Genomic Data. Genetics 2019; 213:1007-1045. [PMID: 31558582 PMCID: PMC6827383 DOI: 10.1534/genetics.119.302581] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 09/22/2019] [Indexed: 11/18/2022] Open
Abstract
The majority of empirical population genetic studies have tried to understand the evolutionary processes that have shaped genetic variation in a single sample taken from a present-day population. However, genomic data collected over tens of generations in both natural and laboratory populations are increasingly used to find selected loci underpinning adaptation over these short timescales. Although these studies have been quite successful in detecting selection on large-effect loci, the fitness differences between individuals are often polygenic, such that selection leads to allele frequency changes that are difficult to distinguish from genetic drift. However, one promising signal comes from polygenic selection's effect on neutral sites that become stochastically associated with the genetic backgrounds that lead to fitness differences between individuals. Previous theoretical work has established that the random associations between a neutral allele and heritable fitness backgrounds act to reduce the effective population size experienced by this neutral allele. These associations perturb neutral allele frequency trajectories, creating autocovariance in the allele frequency changes across generations. Here, we show how temporal genomic data allow us to measure the temporal autocovariance in allele frequency changes and characterize the genome-wide impact of polygenic selection. We develop expressions for these temporal autocovariances, showing that their magnitude is determined by the level of additive genetic variation, recombination, and linkage disequilibria in a region. Furthermore, by using analytic expressions for the temporal variances and autocovariances in allele frequency, we demonstrate that one can estimate the additive genetic variation for fitness and the drift-effective population size from temporal genomic data. We also show how the proportion of total variation in allele frequency change due to linked selection can be estimated from temporal data. Overall, we demonstrate that temporal genomic data offer opportunities to identify the role of linked selection on genome-wide diversity over short timescales, and can help bridge population genetic and quantitative genetic studies of adaptation.
Collapse
Affiliation(s)
- Vince Buffalo
- Population Biology Graduate Group, University of California, Davis, California 95616
- Center for Population Biology, Department of Evolution and Ecology, University of California, Davis, California 95616
| | - Graham Coop
- Center for Population Biology, Department of Evolution and Ecology, University of California, Davis, California 95616
| |
Collapse
|
37
|
Mattila TM, Laenen B, Horvath R, Hämälä T, Savolainen O, Slotte T. Impact of demography on linked selection in two outcrossing Brassicaceae species. Ecol Evol 2019; 9:9532-9545. [PMID: 31534673 PMCID: PMC6745670 DOI: 10.1002/ece3.5463] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 12/13/2022] Open
Abstract
Genetic diversity is shaped by mutation, genetic drift, gene flow, recombination, and selection. The dynamics and interactions of these forces shape genetic diversity across different parts of the genome, between populations and species. Here, we have studied the effects of linked selection on nucleotide diversity in outcrossing populations of two Brassicaceae species, Arabidopsis lyrata and Capsella grandiflora, with contrasting demographic history. In agreement with previous estimates, we found evidence for a modest population size expansion thousands of generations ago, as well as efficient purifying selection in C. grandiflora. In contrast, the A. lyrata population exhibited evidence for very recent strong population size decline and weaker efficacy of purifying selection. Using multiple regression analyses with recombination rate and other genomic covariates as explanatory variables, we can explain 47% of the variance in neutral diversity in the C. grandiflora population, while in the A. lyrata population, only 11% of the variance was explained by the model. Recombination rate had a significant positive effect on neutral diversity in both species, suggesting that selection at linked sites has an effect on patterns of neutral variation. In line with this finding, we also found reduced neutral diversity in the vicinity of genes in the C. grandiflora population. However, in A. lyrata no such reduction in diversity was evident, a finding that is consistent with expectations of the impact of a recent bottleneck on patterns of neutral diversity near genes. This study thus empirically demonstrates how differences in demographic history modulate the impact of selection at linked sites in natural populations.
Collapse
Affiliation(s)
- Tiina M. Mattila
- Department of Ecology and GeneticsUniversity of OuluOuluFinland
- Present address:
Department of Organismal BiologyUppsala UniversityUppsalaSweden
| | - Benjamin Laenen
- Science for Life Laboratory, Department of Ecology, Environment, and Plant SciencesStockholm UniversityStockholmSweden
| | - Robert Horvath
- Science for Life Laboratory, Department of Ecology, Environment, and Plant SciencesStockholm UniversityStockholmSweden
| | - Tuomas Hämälä
- Department of Ecology and GeneticsUniversity of OuluOuluFinland
- Biocenter OuluUniversity of OuluOuluFinland
- Present address:
Department of Plant and Microbial BiologyUniversity of Minnesota Twin CitiesSt. PaulMNUSA
| | - Outi Savolainen
- Department of Ecology and GeneticsUniversity of OuluOuluFinland
- Biocenter OuluUniversity of OuluOuluFinland
| | - Tanja Slotte
- Science for Life Laboratory, Department of Ecology, Environment, and Plant SciencesStockholm UniversityStockholmSweden
| |
Collapse
|
38
|
Washburn JD, McElfresh MJ, Birchler JA. Progressive heterosis in genetically defined tetraploid maize. J Genet Genomics 2019; 46:389-396. [PMID: 31444136 DOI: 10.1016/j.jgg.2019.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 01/24/2019] [Accepted: 02/20/2019] [Indexed: 12/30/2022]
Abstract
Progressive heterosis, i.e., the additional hybrid vigor in double-cross tetraploid hybrids not found in their single-cross tetraploid parents, has been documented in a number of species including alfalfa, potato, and maize. In this study, four artificially induced maize tetraploids, directly derived from standard inbred lines, were crossed in pairs to create two single-cross hybrids. These hybrids were then crossed to create double-cross hybrids containing genetic material from all four original lines. Replicated field-based phenotyping of the materials over four years indicated a strong progressive heterosis phenotype in tetraploids but not in their diploid counterparts. In particular, the above ground dry weight phenotype of double-cross tetraploid hybrids was on average 34% and 56% heavier than that of the single-cross tetraploid hybrids and the double-cross diploid counterparts, respectively. Additionally, whole-genome resequencing of the original inbred lines and further analysis of these data did not show the expected spectrum of alleles to explain tetraploid progressive heterosis under the complementation of complete recessive model. These results underscore the reality of the progressive heterosis phenotype, its potential utility for increasing crop biomass production, and the need for exploring alternative hypothesis to explain it at a molecular level.
Collapse
Affiliation(s)
- Jacob D Washburn
- Division of Biological Sciences, University of Missouri, 311 Tucker Hall, Columbia, MO, 65211, USA
| | - Mitchell J McElfresh
- Division of Biological Sciences, University of Missouri, 311 Tucker Hall, Columbia, MO, 65211, USA
| | - James A Birchler
- Division of Biological Sciences, University of Missouri, 311 Tucker Hall, Columbia, MO, 65211, USA.
| |
Collapse
|
39
|
Booker TR, Keightley PD. Understanding the Factors That Shape Patterns of Nucleotide Diversity in the House Mouse Genome. Mol Biol Evol 2019; 35:2971-2988. [PMID: 30295866 PMCID: PMC6278861 DOI: 10.1093/molbev/msy188] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A major goal of population genetics has been to determine the extent by which selection at linked sites influences patterns of neutral nucleotide diversity in the genome. Multiple lines of evidence suggest that diversity is influenced by both positive and negative selection. For example, in many species there are troughs in diversity surrounding functional genomic elements, consistent with the action of either background selection (BGS) or selective sweeps. In this study, we investigated the causes of the diversity troughs that are observed in the wild house mouse genome. Using the unfolded site frequency spectrum, we estimated the strength and frequencies of deleterious and advantageous mutations occurring in different functional elements in the genome. We then used these estimates to parameterize forward-in-time simulations of chromosomes, using realistic distributions of functional elements and recombination rate variation in order to determine whether selection at linked sites can explain the observed patterns of nucleotide diversity. The simulations suggest that BGS alone cannot explain the dips in diversity around either exons or conserved noncoding elements. A combination of BGS and selective sweeps produces deeper dips in diversity than BGS alone, but the inferred parameters of selection cannot fully explain the patterns observed in the genome. Our results provide evidence of sweeps shaping patterns of nucleotide diversity across the mouse genome and also suggest that infrequent, strongly advantageous mutations play an important role in this. The limitations of using the unfolded site frequency spectrum for inferring the frequency and effects of advantageous mutations are discussed.
Collapse
Affiliation(s)
- Tom R Booker
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom.,Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Peter D Keightley
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
| |
Collapse
|
40
|
Cheng H, Liu J, Wen J, Nie X, Xu L, Chen N, Li Z, Wang Q, Zheng Z, Li M, Cui L, Liu Z, Bian J, Wang Z, Xu S, Yang Q, Appels R, Han D, Song W, Sun Q, Jiang Y. Frequent intra- and inter-species introgression shapes the landscape of genetic variation in bread wheat. Genome Biol 2019; 20:136. [PMID: 31300020 PMCID: PMC6624984 DOI: 10.1186/s13059-019-1744-x] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 06/22/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Bread wheat is one of the most important and broadly studied crops. However, due to the complexity of its genome and incomplete genome collection of wild populations, the bread wheat genome landscape and domestication history remain elusive. RESULTS By investigating the whole-genome resequencing data of 93 accessions from worldwide populations of bread wheat and its diploid and tetraploid progenitors, together with 90 published exome-capture data, we find that the B subgenome has more variations than A and D subgenomes, including SNPs and deletions. Population genetics analyses support a monophyletic origin of domesticated wheat from wild emmer in northern Levant, with substantial introgressed genomic fragments from southern Levant. Southern Levant contributes more than 676 Mb in AB subgenomes and enriched in the pericentromeric regions. The AB subgenome introgression happens at the early stage of wheat speciation and partially contributes to their greater genetic diversity. Furthermore, we detect massive alien introgressions that originated from distant species through natural and artificial hybridizations, resulting in the reintroduction of ~ 709 Mb and ~ 1577 Mb sequences into bread wheat landraces and varieties, respectively. A large fraction of these intra- and inter-introgression fragments are associated with quantitative trait loci of important traits, and selection events are also identified. CONCLUSION We reveal the significance of multiple introgressions from distant wild populations and alien species in shaping the genetic components of bread wheat, and provide important resources and new perspectives for future wheat breeding.
Collapse
Affiliation(s)
- Hong Cheng
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Jing Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
- Department of Molecular Evolution and Development, University of Vienna, Vienna, Austria
| | - Jia Wen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Xiaojun Nie
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Luohao Xu
- Department of Molecular Evolution and Development, University of Vienna, Vienna, Austria
| | - Ningbo Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Zhongxing Li
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Horticulture, Northwest A&F University, Yangling, 712100 China
| | - Qilin Wang
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Zhuqing Zheng
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Ming Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Licao Cui
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Zihua Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| | - Jianxin Bian
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Zhonghua Wang
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Shengbao Xu
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Qin Yang
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Rudi Appels
- AgriBio, Centre for AgriBioscience, Department of Economic Development, Jobs, Transport, and Resources, La Trobe University, 5 Ring Road, Bundoora, VIC 3083 Australia
| | - Dejun Han
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Weining Song
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
| | - Qixin Sun
- State Key Laboratory of Crop Stress Biology in Arid Areas, College of Agronomy, Northwest A&F University, Yangling, 712100 China
- College of Agronomy and Biotechnology, China Agricultural University, Beijing, 100193 China
| | - Yu Jiang
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 China
| |
Collapse
|
41
|
Wang J, Li X, Do Kim K, Scanlon MJ, Jackson SA, Springer NM, Yu J. Genome-wide nucleotide patterns and potential mechanisms of genome divergence following domestication in maize and soybean. Genome Biol 2019; 20:74. [PMID: 31018867 PMCID: PMC6482504 DOI: 10.1186/s13059-019-1683-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 03/28/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Plant domestication provides a unique model to study genome evolution. Many studies have been conducted to examine genes, genetic diversity, genome structure, and epigenome changes associated with domestication. Interestingly, domesticated accessions have significantly higher [A] and [T] values across genome-wide polymorphic sites than accessions sampled from the corresponding progenitor species. However, the relative contributions of different genomic regions to this genome divergence pattern and underlying mechanisms have not been well characterized. RESULTS Here, we investigate the genome-wide base-composition patterns by analyzing millions of SNPs segregating among 100 accessions from a teosinte-maize comparison set and among 302 accessions from a wild-domesticated soybean comparison set. We show that non-genic part of the genome has a greater contribution than genic SNPs to the [AT]-increase observed between wild and domesticated accessions in maize and soybean. The separation between wild and domesticated accessions in [AT] values is significantly enlarged in non-genic and pericentromeric regions. Motif frequency and sequence context analyses show the motifs (PyCG) related to solar-UV signature are enriched in these regions, particularly when they are methylated. Additional analysis using population-private SNPs also implicates the role of these motifs in relatively recent mutations. With base-composition across polymorphic sites as a genome phenotype, genome scans identify a set of putative candidate genes involved in UV damage repair pathways. CONCLUSIONS The [AT]-increase is more pronounced in genomic regions that are non-genic, pericentromeric, transposable elements; methylated; and with low recombination. Our findings establish important links among UV radiation, mutation, DNA repair, methylation, and genome evolution.
Collapse
Affiliation(s)
- Jinyu Wang
- Department of Agronomy, Iowa State University, Ames, IA 50011 USA
| | - Xianran Li
- Department of Agronomy, Iowa State University, Ames, IA 50011 USA
| | - Kyung Do Kim
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA 30602 USA
| | - Michael J. Scanlon
- Plant Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853 USA
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA 30602 USA
| | - Nathan M. Springer
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN 55108 USA
| | - Jianming Yu
- Department of Agronomy, Iowa State University, Ames, IA 50011 USA
| |
Collapse
|
42
|
Xu S, Stapley J, Gablenz S, Boyer J, Appenroth KJ, Sree KS, Gershenzon J, Widmer A, Huber M. Low genetic variation is associated with low mutation rate in the giant duckweed. Nat Commun 2019; 10:1243. [PMID: 30886148 PMCID: PMC6423293 DOI: 10.1038/s41467-019-09235-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 02/27/2019] [Indexed: 12/30/2022] Open
Abstract
Mutation rate and effective population size (Ne) jointly determine intraspecific genetic diversity, but the role of mutation rate is often ignored. Here we investigate genetic diversity, spontaneous mutation rate and Ne in the giant duckweed (Spirodela polyrhiza). Despite its large census population size, whole-genome sequencing of 68 globally sampled individuals reveals extremely low intraspecific genetic diversity. Assessed under natural conditions, the genome-wide spontaneous mutation rate is at least seven times lower than estimates made for other multicellular eukaryotes, whereas Ne is large. These results demonstrate that low genetic diversity can be associated with large-Ne species, where selection can reduce mutation rates to very low levels. This study also highlights that accurate estimates of mutation rate can help to explain seemingly unexpected patterns of genome-wide variation.
Collapse
Affiliation(s)
- Shuqing Xu
- Institute for Evolution and Biodiversity, University of Münster, Hüfferstrasse 1, 48149, Münster, Germany.
| | - Jessica Stapley
- Center for Adaptation to a Changing Environment, ETH Zurich, Universitätstrasse 16, 8092, Zürich, Switzerland
| | - Saskia Gablenz
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Justin Boyer
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Klaus J Appenroth
- Matthias-Schleiden-Institute, Plant Physiology, Friedrich Schiller University of Jena, Dornburgerstraße 159, 07743, Jena, Germany
| | - K Sowjanya Sree
- Department of Environmental Science, Central University of Kerala, Periye, 671316, India
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Alex Widmer
- Institute of Integrative Biology, ETH Zurich, Universitätstrasse 16, 8092, Zürich, Switzerland
| | - Meret Huber
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany.
- Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 7, 48143, Münster, Germany.
| |
Collapse
|
43
|
Liang Z, Duan S, Sheng J, Zhu S, Ni X, Shao J, Liu C, Nick P, Du F, Fan P, Mao R, Zhu Y, Deng W, Yang M, Huang H, Liu Y, Ding Y, Liu X, Jiang J, Zhu Y, Li S, He X, Chen W, Dong Y. Whole-genome resequencing of 472 Vitis accessions for grapevine diversity and demographic history analyses. Nat Commun 2019; 10:1190. [PMID: 30867414 PMCID: PMC6416300 DOI: 10.1038/s41467-019-09135-8] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 02/21/2019] [Indexed: 01/27/2023] Open
Abstract
Understanding the Vitis species at the genomic level is important for cultivar improvement of grapevine. Here we report whole-genome genetic variation at single-base resolution of 472 Vitis accessions, which cover 48 out of 60 extant Vitis species from a wide geographic distribution. The variation helps to identify a recent dramatic expansion and contraction of effective population size in the domesticated grapevines and that cultivars from the pan-Black Sea region have a unique demographic history in comparison to the other domesticated cultivars. We also find selective sweeps for berry edibility and stress resistance improvement. Furthermore, we find associations between candidate genes and important agronomic traits, such as berry shape and aromatic compounds. These results demonstrate resource value of the resequencing data for illuminating the evolutionary biology of Vitis species and providing targets for grapevine genetic improvement. Despite the importance of grapevine cultivation in human history and the economic values of cultivar improvement, large-scale genomic variation data are lacking. Here the authors resequence 472 Vitis accessions and use the identified genetic variations for domestication history, demography, and GWAS analyses.
Collapse
Affiliation(s)
- Zhenchang Liang
- Beijing Key Laboratory of Grape Sciences and Enology, Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.,Sino-Africa Joint Research Center, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Shengchang Duan
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China.,Nowbio Biotechnology Company, Kunming, 650201, China
| | - Jun Sheng
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China.,Yunnan Research Institute for Local Plateau Agriculture and Industry, Kunming, 650201, China.,Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Shusheng Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China.,Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Xuemei Ni
- BGI, BGI-Shenzhen, Shenzhen, 518120, China.,BGI Institute of Applied Agriculture, BGI-Shenzhen, Shenzhen, 518120, China
| | - Jianhui Shao
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Chonghuai Liu
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009, China
| | - Peter Nick
- Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe, 76128, Germany
| | - Fei Du
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Peige Fan
- Beijing Key Laboratory of Grape Sciences and Enology, Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Ruzhi Mao
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Yifan Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China.,Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Weiping Deng
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Min Yang
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Huichuan Huang
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Yixiang Liu
- Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Yiqing Ding
- Beijing Key Laboratory of Grape Sciences and Enology, Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xianju Liu
- Beijing Key Laboratory of Grape Sciences and Enology, Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jianfu Jiang
- Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou, 450009, China
| | - Youyong Zhu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China.,Yunnan Research Institute for Local Plateau Agriculture and Industry, Kunming, 650201, China.,Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China
| | - Shaohua Li
- Beijing Key Laboratory of Grape Sciences and Enology, Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Xiahong He
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China. .,Key Laboratory for Agro-biodiversity and Pest Control of Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China.
| | - Wei Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China. .,Yunnan Research Institute for Local Plateau Agriculture and Industry, Kunming, 650201, China.
| | - Yang Dong
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming, 650201, China. .,Yunnan Research Institute for Local Plateau Agriculture and Industry, Kunming, 650201, China.
| |
Collapse
|
44
|
Wang X, Chen L, Ma J. Genomic introgression through interspecific hybridization counteracts genetic bottleneck during soybean domestication. Genome Biol 2019; 20:22. [PMID: 30700312 PMCID: PMC6354408 DOI: 10.1186/s13059-019-1631-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 01/16/2019] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Evidence of introgression, the transfer of genetic material, between crops and their wild relatives through spontaneous hybridization and subsequent backcrossing has been documented; however, the evolutionary patterns and consequences of introgression and its influence on the processes of crop domestication and varietal diversification are poorly understood. RESULTS We investigate the genomic landscape and evolution of putative crop-wild-relative introgression by analyzing the nuclear and chloroplast genomes from a panel of wild (Glycine soja) and domesticated (Glycine max) soybeans. Our data suggest that naturally occurring introgression between wild and domesticated soybeans was widespread and that introgressed variation in both wild and domesticated soybeans was selected against throughout the genomes and preferentially removed from the genomic regions underlying selective sweeps and domestication quantitative trait locus (QTL). In both taxa, putative introgression was preferentially retained in recombination-repressed pericentromeric regions that exhibit lower gene densities, reflecting potential roles of recombination in purging introgression. Despite extensive removal of introgressed variation by recurrent selection for domestication-related QTL and associated genomic regions, spontaneous interspecific hybridization during soybean domestication appear to have contributed to a rapid varietal diversification with high levels of genetic diversity and asymmetric evolution between the nuclear and chloroplast genomes. CONCLUSIONS This work reveals the evolutionary forces, patterns, and consequences of putative genomic introgression between crops and their wild relatives, and the effects of introgression on the processes of crop domestication and varietal diversification. We envision that interspecific introgression serves as an important mechanism for counteracting the reduction of genetic diversity in domesticated crops, particularly the ones under single domestication.
Collapse
Affiliation(s)
- Xutong Wang
- Department of Agronomy, Purdue University, West Lafayette, IN 47907 USA
| | - Liyang Chen
- Department of Agronomy, Purdue University, West Lafayette, IN 47907 USA
| | - Jianxin Ma
- Department of Agronomy, Purdue University, West Lafayette, IN 47907 USA
| |
Collapse
|
45
|
Wallace JG, Rodgers-Melnick E, Buckler ES. On the Road to Breeding 4.0: Unraveling the Good, the Bad, and the Boring of Crop Quantitative Genomics. Annu Rev Genet 2018; 52:421-444. [DOI: 10.1146/annurev-genet-120116-024846] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Understanding the quantitative genetics of crops has been and will continue to be central to maintaining and improving global food security. We outline four stages that plant breeding either has already achieved or will probably soon achieve. Top-of-the-line breeding programs are currently in Breeding 3.0, where inexpensive, genome-wide data coupled with powerful algorithms allow us to start breeding on predicted instead of measured phenotypes. We focus on three major questions that must be answered to move from current Breeding 3.0 practices to Breeding 4.0: ( a) How do we adapt crops to better fit agricultural environments? ( b) What is the nature of the diversity upon which breeding can act? ( c) How do we deal with deleterious variants? Answering these questions and then translating them to actual gains for farmers will be a significant part of achieving global food security in the twenty-first century.
Collapse
Affiliation(s)
- Jason G. Wallace
- Department of Crop and Soil Sciences, The University of Georgia, Athens, Georgia 30602, USA
| | | | - Edward S. Buckler
- United States Department of Agriculture, Agricultural Research Service, Ithaca, New York 14853, USA
- Institute for Genomic Diversity, Cornell University, Ithaca, New York 14853, USA
| |
Collapse
|
46
|
Blischak PD, Mabry ME, Conant GC, Pires JC. Integrating Networks, Phylogenomics, and Population Genomics for the Study of Polyploidy. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2018. [DOI: 10.1146/annurev-ecolsys-121415-032302] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Duplication events are regarded as sources of evolutionary novelty, but our understanding of general trends for the long-term trajectory of additional genomic material is still lacking. Organisms with a history of whole genome duplication (WGD) offer a unique opportunity to study potential trends in the context of gene retention and/or loss, gene and network dosage, and changes in gene expression. In this review, we discuss the prevalence of polyploidy across the tree of life, followed by an overview of studies investigating genome evolution and gene expression. We then provide an overview of methods in network biology, phylogenomics, and population genomics that are critical for advancing our understanding of evolution post-WGD, highlighting the need for models that can accommodate polyploids. Finally, we close with a brief note on the importance of random processes in the evolution of polyploids with respect to neutral versus selective forces, ancestral polymorphisms, and the formation of autopolyploids versus allopolyploids.
Collapse
Affiliation(s)
- Paul D. Blischak
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Makenzie E. Mabry
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211, USA
| | - Gavin C. Conant
- Division of Animal Sciences, University of Missouri, Columbia, Missouri 65211, USA
- Current affiliation: Bioinformatics Research Center, Program in Genetics and Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - J. Chris Pires
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, Missouri 65211-7310, USA
| |
Collapse
|
47
|
Stetter MG, Thornton K, Ross-Ibarra J. Genetic architecture and selective sweeps after polygenic adaptation to distant trait optima. PLoS Genet 2018; 14:e1007794. [PMID: 30452452 PMCID: PMC6277123 DOI: 10.1371/journal.pgen.1007794] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/03/2018] [Accepted: 10/26/2018] [Indexed: 11/22/2022] Open
Abstract
Understanding the genetic basis of phenotypic adaptation to changing environments is an essential goal of population and quantitative genetics. While technological advances now allow interrogation of genome-wide genotyping data in large panels, our understanding of the process of polygenic adaptation is still limited. To address this limitation, we use extensive forward-time simulation to explore the impacts of variation in demography, trait genetics, and selection on the rate and mode of adaptation and the resulting genetic architecture. We simulate a population adapting to an optimum shift, modeling sequence variation for 20 QTL for each of 12 different demographies for 100 different traits varying in the effect size distribution of new mutations, the strength of stabilizing selection, and the contribution of the genomic background. We then use random forest regression approaches to learn the relative importance of input parameters in determining a number of aspects of the process of adaptation, including the speed of adaptation, the relative frequency of hard sweeps and sweeps from standing variation, or the final genetic architecture of the trait. We find that selective sweeps occur even for traits under relatively weak selection and where the genetic background explains most of the variation. Though most sweeps occur from variation segregating in the ancestral population, new mutations can be important for traits under strong stabilizing selection that undergo a large optimum shift. We also show that population bottlenecks and expansion impact overall genetic variation as well as the relative importance of sweeps from standing variation and the speed with which adaptation can occur. We then compare our results to two traits under selection during maize domestication, showing that our simulations qualitatively recapitulate differences between them. Overall, our results underscore the complex population genetics of individual loci in even relatively simple quantitative trait models, but provide a glimpse into the factors that drive this complexity and the potential of these approaches for understanding polygenic adaptation.
Collapse
Affiliation(s)
- Markus G. Stetter
- Dept. of Plant Sciences and Center for Population Biology, University of California, Davis, Davis, CA, USA
| | - Kevin Thornton
- Dept. of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, USA
| | - Jeffrey Ross-Ibarra
- Dept. of Plant Sciences and Center for Population Biology, University of California, Davis, Davis, CA, USA
- Genome Center, University of California, Davis, Davis, CA, USA
| |
Collapse
|
48
|
Cornejo OE, Yee MC, Dominguez V, Andrews M, Sockell A, Strandberg E, Livingstone D, Stack C, Romero A, Umaharan P, Royaert S, Tawari NR, Ng P, Gutierrez O, Phillips W, Mockaitis K, Bustamante CD, Motamayor JC. Population genomic analyses of the chocolate tree, Theobroma cacao L., provide insights into its domestication process. Commun Biol 2018; 1:167. [PMID: 30345393 PMCID: PMC6191438 DOI: 10.1038/s42003-018-0168-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 09/14/2018] [Indexed: 01/24/2023] Open
Abstract
Domestication has had a strong impact on the development of modern societies. We sequenced 200 genomes of the chocolate plant Theobroma cacao L. to show for the first time to our knowledge that a single population, the Criollo population, underwent strong domestication ~3600 years ago (95% CI: 2481-13,806 years ago). We also show that during the process of domestication, there was strong selection for genes involved in the metabolism of the colored protectants anthocyanins and the stimulant theobromine, as well as disease resistance genes. Our analyses show that domesticated populations of T. cacao (Criollo) maintain a higher proportion of high-frequency deleterious mutations. We also show for the first time the negative consequences of the increased accumulation of deleterious mutations during domestication on the fitness of individuals (significant reduction in kilograms of beans per hectare per year as Criollo ancestry increases, as estimated from a GLM, P = 0.000425).
Collapse
Affiliation(s)
- Omar E Cornejo
- School of Biological Sciences, Washington State University, PO Box 644236, Heald Hall 429B, Pullman, Washington, 99164, USA
- Department of Genetics, School of Medicine, Stanford University, 300 Pasteur Dr. Lane Bldg Room L331, Stanford, CA, 94305, USA
| | - Muh-Ching Yee
- Department of Genetics, School of Medicine, Stanford University, 300 Pasteur Dr. Lane Bldg Room L331, Stanford, CA, 94305, USA
- Stanford Functional Genomics Facility, Stanford, CA, 94305, USA
| | - Victor Dominguez
- Department of Biology, Indiana University, 915 E. Third St, Bloomington, IN, 47405, USA
| | - Mary Andrews
- Department of Biology, Indiana University, 915 E. Third St, Bloomington, IN, 47405, USA
| | - Alexandra Sockell
- Department of Genetics, School of Medicine, Stanford University, 300 Pasteur Dr. Lane Bldg Room L331, Stanford, CA, 94305, USA
| | - Erika Strandberg
- Department of Genetics, School of Medicine, Stanford University, 300 Pasteur Dr. Lane Bldg Room L331, Stanford, CA, 94305, USA
- Biomedical Informatics Training Program, 1265 Welch Road, MSOB, X-215, MC 5479, Stanford, CA, 94305-5479, USA
| | - Donald Livingstone
- Mars, Incorporated, 6885 Elm Street, McLean, VA, 22101, USA
- United States Department of Agriculture-Agriculture Research Service, Subtropical Horticulture Research Station, 13601 Old Cutler Rd, Miami, FL, 33158, USA
| | - Conrad Stack
- Mars, Incorporated, 6885 Elm Street, McLean, VA, 22101, USA
| | - Alberto Romero
- Mars, Incorporated, 6885 Elm Street, McLean, VA, 22101, USA
| | - Pathmanathan Umaharan
- Cocoa Research Centre, The University of the West Indies, St. Augustine, Trinidad and Tobago
| | - Stefan Royaert
- Mars, Incorporated, 6885 Elm Street, McLean, VA, 22101, USA
| | - Nilesh R Tawari
- Computational and Systems Biology, Genome Institute of Singapore, 60 Biopolis Street, Genome, #02-01, Singapore, 138672, Singapore
| | - Pauline Ng
- Computational and Systems Biology, Genome Institute of Singapore, 60 Biopolis Street, Genome, #02-01, Singapore, 138672, Singapore
| | - Osman Gutierrez
- SHRS, USDS-ARS, 13601 Old Cutler Road, Miami, FL, 33158, USA
| | - Wilbert Phillips
- Programa de Mejoramiento de Cacao, CATIE, 7170, Turrialba, Costa Rica
| | - Keithanne Mockaitis
- Department of Biology, Indiana University, 915 E. Third St, Bloomington, IN, 47405, USA
- Pervasive Technology Institute, Indiana University, 2709 E. 10th St., Bloomington, IN, 47408, USA
| | - Carlos D Bustamante
- Department of Genetics, School of Medicine, Stanford University, 300 Pasteur Dr. Lane Bldg Room L331, Stanford, CA, 94305, USA
| | | |
Collapse
|
49
|
Stitzer MC, Ross-Ibarra J. Maize domestication and gene interaction. THE NEW PHYTOLOGIST 2018; 220:395-408. [PMID: 30035321 DOI: 10.1111/nph.15350] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 06/05/2018] [Indexed: 05/24/2023]
Abstract
Contents Summary 395 I. Introduction 395 II. The genetic basis of maize domestication 396 III. The tempo of maize domestication 401 IV. Genetic interactions and selection during maize domestication 401 V. Gene networks of maize domestication alleles 404 VI. Implications of gene interactions on evolution and selection404 VII. Conclusions 405 Acknowledgements 405 References 405 SUMMARY: Domestication is a tractable system for following evolutionary change. Under domestication, wild populations respond to shifting selective pressures, resulting in adaptation to the new ecological niche of cultivation. Owing to the important role of domesticated crops in human nutrition and agriculture, the ancestry and selection pressures transforming a wild plant into a domesticate have been extensively studied. In Zea mays, morphological, genetic and genomic studies have elucidated how a wild plant, the teosinte Z. mays subsp. parviglumis, was transformed into the domesticate Z. mays subsp. mays. Five major morphological differences distinguish these two subspecies, and careful genetic dissection has pinpointed the molecular changes responsible for several of these traits. But maize domestication was a consequence of more than just five genes, and regions throughout the genome contribute. The impacts of these additional regions are contingent on genetic background, both the interactions between alleles of a single gene and among alleles of the multiple genes that modulate phenotypes. Key genetic interactions include dominance relationships, epistatic interactions and pleiotropic constraint, including how these variants are connected in gene networks. Here, we review the role of gene interactions in generating the dramatic phenotypic evolution seen in the transition from teosinte to maize.
Collapse
Affiliation(s)
- Michelle C Stitzer
- Department of Plant Sciences, University of California, Davis, Davis, CA, 95616, USA
- Center for Population Biology, University of California, Davis, Davis, CA, 95616, USA
| | - Jeffrey Ross-Ibarra
- Department of Plant Sciences, University of California, Davis, Davis, CA, 95616, USA
- Center for Population Biology, University of California, Davis, Davis, CA, 95616, USA
- Genome Center, University of California, Davis, Davis, CA, 95616, USA
| |
Collapse
|
50
|
Guo L, Wang X, Zhao M, Huang C, Li C, Li D, Yang CJ, York AM, Xue W, Xu G, Liang Y, Chen Q, Doebley JF, Tian F. Stepwise cis-Regulatory Changes in ZCN8 Contribute to Maize Flowering-Time Adaptation. Curr Biol 2018; 28:3005-3015.e4. [PMID: 30220503 PMCID: PMC6537595 DOI: 10.1016/j.cub.2018.07.029] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 05/24/2018] [Accepted: 07/09/2018] [Indexed: 12/28/2022]
Abstract
Maize (Zea mays ssp. mays) was domesticated in southwestern Mexico ∼9,000 years ago from its wild ancestor, teosinte (Zea mays ssp. parviglumis) [1]. From its center of origin, maize experienced a rapid range expansion and spread over 90° of latitude in the Americas [2-4], which required a novel flowering-time adaptation. ZEA CENTRORADIALIS 8 (ZCN8) is the maize florigen gene and has a central role in mediating flowering [5, 6]. Here, we show that ZCN8 underlies a major quantitative trait locus (QTL) (qDTA8) for flowering time that was consistently detected in multiple maize-teosinte experimental populations. Through association analysis in a large diverse panel of maize inbred lines, we identified a SNP (SNP-1245) in the ZCN8 promoter that showed the strongest association with flowering time. SNP-1245 co-segregated with qDTA8 in maize-teosinte mapping populations. We demonstrate that SNP-1245 is associated with differential binding by the flowering activator ZmMADS1. SNP-1245 was a target of selection during early domestication, which drove the pre-existing early flowering allele to near fixation in maize. Interestingly, we detected an independent association block upstream of SNP-1245, wherein the early flowering allele that most likely originated from Zea mays ssp. mexicana introgressed into the early flowering haplotype of SNP-1245 and contributed to maize adaptation to northern high latitudes. Our study demonstrates how independent cis-regulatory variants at a gene can be selected at different evolutionary times for local adaptation, highlighting how complex cis-regulatory control mechanisms evolve. Finally, we propose a polygenic map for the pre-Columbian spread of maize throughout the Americas.
Collapse
Affiliation(s)
- Li Guo
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Xuehan Wang
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Min Zhao
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Cheng Huang
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Cong Li
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Dan Li
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Chin Jian Yang
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Alessandra M York
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Wei Xue
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Guanghui Xu
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Yameng Liang
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China
| | - Qiuyue Chen
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China; Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - John F Doebley
- Department of Genetics, University of Wisconsin, Madison, WI 53706, USA
| | - Feng Tian
- National Maize Improvement Center, Key Laboratory of Biology and Genetic Improvement of Maize (MOA), Beijing Key Laboratory of Crop Genetic Improvement, Joint International Research Laboratory of Crop Molecular Breeding, China Agricultural University, Beijing 100193, China.
| |
Collapse
|