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Cohen ZP, Schoville SD, Hawthorne DJ. The role of structural variants in pest adaptation and genome evolution of the Colorado potato beetle, Leptinotarsa decemlineata (Say). Mol Ecol 2023; 32:1425-1440. [PMID: 36591939 DOI: 10.1111/mec.16838] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/30/2022] [Accepted: 12/15/2022] [Indexed: 01/03/2023]
Abstract
Structural variation has been associated with genetic diversity and adaptation. Despite these observations, it is not clear what their relative importance is for evolution, especially in rapidly adapting species. Here, we examine the significance of structural polymorphisms in pesticide resistance evolution of the agricultural super-pest, the Colorado potato beetle, Leptinotarsa decemlineata. By employing a parent offspring trio sequencing procedure, we develop highly contiguous reference genomes to characterize structural variation. These updated assemblies represent >100-fold improvement of contiguity and include derived pest and ancestral nonpest individuals. We identify >200,000 structural variations, which appear to be nonrandomly distributed across the genome as they co-occur with transposable elements and genes. Structural variations intersect with exons in a large proportion of gene annotations (~20%) that are associated with insecticide resistance (including cytochrome P450s), development, and transcription. To understand the role structural variations play in adaptation, we measure their allele frequencies among an additional 57 individuals using whole genome resequencing data, which represents pest and nonpest populations of North America. Incorporating multiple independent tests to detect the signature of natural selection using SNP data, we identify 14 genes that are probably under positive selection, include structural variations, and SNPs of elevated frequency within the pest lineages. Among these, three are associated with insecticide resistance based on previous research. One of these genes, CYP4g15, is coinduced during insecticide exposure with glycosyltransferase-13, which is a duplicated gene enclosed within a structural variant adjacent to the CYP4g15 genic region. These results demonstrate the significance of structural variations as a genomic feature to describe species history, genetic diversity, and adaptation.
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Affiliation(s)
- Zachary P Cohen
- Department of Entomology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Sean D Schoville
- Department of Entomology, University of Wisconsin-Madison, Madison, Wisconsin, USA
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2
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Verbiest M, Maksimov M, Jin Y, Anisimova M, Gymrek M, Bilgin Sonay T. Mutation and selection processes regulating short tandem repeats give rise to genetic and phenotypic diversity across species. J Evol Biol 2023; 36:321-336. [PMID: 36289560 PMCID: PMC9990875 DOI: 10.1111/jeb.14106] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 06/29/2022] [Accepted: 08/01/2022] [Indexed: 02/03/2023]
Abstract
Short tandem repeats (STRs) are units of 1-6 bp that repeat in a tandem fashion in DNA. Along with single nucleotide polymorphisms and large structural variations, they are among the major genomic variants underlying genetic, and likely phenotypic, divergence. STRs experience mutation rates that are orders of magnitude higher than other well-studied genotypic variants. Frequent copy number changes result in a wide range of alleles, and provide unique opportunities for modulating complex phenotypes through variation in repeat length. While classical studies have identified key roles of individual STR loci, the advent of improved sequencing technology, high-quality genome assemblies for diverse species, and bioinformatics methods for genome-wide STR analysis now enable more systematic study of STR variation across wide evolutionary ranges. In this review, we explore mutation and selection processes that affect STR copy number evolution, and how these processes give rise to varying STR patterns both within and across species. Finally, we review recent examples of functional and adaptive changes linked to STRs.
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Affiliation(s)
- Max Verbiest
- Institute of Computational Life Sciences, School of Life Sciences and Facility ManagementZürich University of Applied SciencesWädenswilSwitzerland
- Department of Molecular Life SciencesUniversity of ZurichZurichSwitzerland
- Swiss Institute of BioinformaticsLausanneSwitzerland
| | - Mikhail Maksimov
- Department of Computer Science & EngineeringUniversity of California San DiegoLa JollaCaliforniaUSA
- Department of MedicineUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Ye Jin
- Department of MedicineUniversity of California San DiegoLa JollaCaliforniaUSA
- Department of BioengineeringUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Maria Anisimova
- Institute of Computational Life Sciences, School of Life Sciences and Facility ManagementZürich University of Applied SciencesWädenswilSwitzerland
- Swiss Institute of BioinformaticsLausanneSwitzerland
| | - Melissa Gymrek
- Department of Computer Science & EngineeringUniversity of California San DiegoLa JollaCaliforniaUSA
- Department of MedicineUniversity of California San DiegoLa JollaCaliforniaUSA
| | - Tugce Bilgin Sonay
- Institute of Ecology, Evolution and Environmental BiologyColumbia UniversityNew YorkNew YorkUSA
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Ranathunge C, Chimahusky ME, Welch ME. A comparative study of population genetic structure reveals patterns consistent with selection at functional microsatellites in common sunflower. Mol Genet Genomics 2022; 297:1329-1342. [PMID: 35786764 DOI: 10.1007/s00438-022-01920-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2021] [Accepted: 06/16/2022] [Indexed: 10/17/2022]
Abstract
Microsatellites, also known as short tandem repeats (STRs), have long been considered non-functional, neutrally evolving regions of the genome. Recent findings suggest that they can function as drivers of rapid adaptive evolution. Previous work on the common sunflower identified 479 transcribed microsatellites where allele length significantly correlates with gene expression (eSTRs) in a stepwise manner. Here, a population genetic approach is used to test whether eSTR allele length variation is under selection. Genotypic variation among and within populations at 13 eSTRs was compared with that at 19 anonymous microsatellites in 672 individuals from 17 natural populations of sunflower from across a cline running from Saskatchewan to Oklahoma (distance of approximately 1600 km). Expected heterozygosity, allelic richness, and allelic diversity were significantly lower at eSTRs, a pattern consistent with higher relative rates of purifying selection. Further, an analysis of variation in microsatellite allele lengths (lnRV), and heterozygosities (lnRH), indicate recent selective sweeps at the eSTRs. Mean microsatellite allele lengths at four eSTRs within populations are significantly correlated with latitude consistent with the predictions of the tuning-knob model which predicts stepwise relationships between microsatellite allele length and phenotypes. This finding suggests that shorter or longer alleles at eSTRs may be favored in climatic extremes. Collectively, our results imply that eSTRs are likely under selection and that they may be playing a role in facilitating local adaptation across a well-defined cline in the common sunflower.
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Affiliation(s)
- Chathurani Ranathunge
- Department of Biological Sciences, Mississippi State University, Starkville, MS, 39762, USA.
- School of Health Professions, Eastern Virginia Medical School, Norfolk, VA, 23507, USA.
| | - Melody E Chimahusky
- Department of Biological Sciences, Mississippi State University, Starkville, MS, 39762, USA
| | - Mark E Welch
- Department of Biological Sciences, Mississippi State University, Starkville, MS, 39762, USA
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Vavilova VY, Konopatskaia ID, Blinov AG, Kondratenko EY, Kruchinina YV, Goncharov NP. Genetic Variability of Btr1 Genes in Tetraploid Wheat Species and Aegilops speltoides Tausch. RUSS J GENET+ 2022. [DOI: 10.1134/s1022795422060138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abondio P, Cilli E, Luiselli D. Inferring Signatures of Positive Selection in Whole-Genome Sequencing Data: An Overview of Haplotype-Based Methods. Genes (Basel) 2022; 13:genes13050926. [PMID: 35627311 PMCID: PMC9141518 DOI: 10.3390/genes13050926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
Signatures of positive selection in the genome are a characteristic mark of adaptation that can reveal an ongoing, recent, or ancient response to environmental change throughout the evolution of a population. New sources of food, climate conditions, and exposure to pathogens are only some of the possible sources of selective pressure, and the rise of advantageous genetic variants is a crucial determinant of survival and reproduction. In this context, the ability to detect these signatures of selection may pinpoint genetic variants that are responsible for a significant change in gene regulation, gene expression, or protein synthesis, structure, and function. This review focuses on statistical methods that take advantage of linkage disequilibrium and haplotype determination to reveal signatures of positive selection in whole-genome sequencing data, showing that they emerge from different descriptions of the same underlying event. Moreover, considerations are provided around the application of these statistics to different species, their suitability for ancient DNA, and the usefulness of discovering variants under selection for biomedicine and public health in an evolutionary medicine framework.
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Affiliation(s)
- Paolo Abondio
- Department of Cultural Heritage, University of Bologna, Via Degli Ariani 1, 48121 Ravenna, Italy; (E.C.); (D.L.)
- Laboratory of Molecular Anthropology and Center for Genome Biology, Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Selmi 3, 40126 Bologna, Italy
- Correspondence:
| | - Elisabetta Cilli
- Department of Cultural Heritage, University of Bologna, Via Degli Ariani 1, 48121 Ravenna, Italy; (E.C.); (D.L.)
| | - Donata Luiselli
- Department of Cultural Heritage, University of Bologna, Via Degli Ariani 1, 48121 Ravenna, Italy; (E.C.); (D.L.)
- Fano Marine Center, The Inter-Institute Center for Research on Marine Biodiversity, Resources and Biotechnologies (FMC), Viale Adriatico 1/N, 61032 Fano, Italy
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The evolutionary history of the polyQ tract in huntingtin sheds light on its functional pro-neural activities. Cell Death Differ 2022; 29:293-305. [PMID: 34974533 PMCID: PMC8817008 DOI: 10.1038/s41418-021-00914-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 11/09/2021] [Accepted: 11/24/2021] [Indexed: 12/15/2022] Open
Abstract
Huntington's disease is caused by a pathologically long (>35) CAG repeat located in the first exon of the Huntingtin gene (HTT). While pathologically expanded CAG repeats are the focus of extensive investigations, non-pathogenic CAG tracts in protein-coding genes are less well characterized. Here, we investigated the function and evolution of the physiological CAG tract in the HTT gene. We show that the poly-glutamine (polyQ) tract encoded by CAGs in the huntingtin protein (HTT) is under purifying selection and subjected to stronger selective pressures than CAG-encoded polyQ tracts in other proteins. For natural selection to operate, the polyQ must perform a function. By combining genome-edited mouse embryonic stem cells and cell assays, we show that small variations in HTT polyQ lengths significantly correlate with cells' neurogenic potential and with changes in the gene transcription network governing neuronal function. We conclude that during evolution natural selection promotes the conservation and purity of the CAG-encoded polyQ tract and that small increases in its physiological length influence neural functions of HTT. We propose that these changes in HTT polyQ length contribute to evolutionary fitness including potentially to the development of a more complex nervous system.
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Analyses of Lysin-motif Receptor-like Kinase ( LysM-RLK) Gene Family in Allotetraploid Brassica napus L. and Its Progenitor Species: An In Silico Study. Cells 2021; 11:cells11010037. [PMID: 35011598 PMCID: PMC8750388 DOI: 10.3390/cells11010037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/10/2021] [Accepted: 12/20/2021] [Indexed: 12/11/2022] Open
Abstract
The LysM receptor-like kinases (LysM-RLKs) play a crucial role in plant symbiosis and response to environmental stresses. Brassica napus, B. rapa, and B. oleracea are utilized as valuable vegetables. Different biotic and abiotic stressors affect these crops, resulting in yield losses. Therefore, genome-wide analysis of the LysM-RLK gene family was conducted. From the genome of the examined species, 33 LysM-RLK have been found. The conserved domains of Brassica LysM-RLKs were divided into three groups: LYK, LYP, and LysMn. In the BrassicaLysM-RLK gene family, only segmental duplication has occurred. The Ka/Ks ratio for the duplicated pair of genes was less than one indicating that the genes’ function had not changed over time. The BrassicaLysM-RLKs contain 70 cis-elements, indicating that they are involved in stress response. 39 miRNA molecules were responsible for the post-transcriptional regulation of 12 Brassica LysM-RLKs. A total of 22 SSR loci were discovered in 16 Brassica LysM-RLKs. According to RNA-seq data, the highest expression in response to biotic stresses was related to BnLYP6. According to the docking simulations, several residues in the active sites of BnLYP6 are in direct contact with the docked chitin and could be useful in future studies to develop pathogen-resistant B. napus. This research reveals comprehensive information that could lead to the identification of potential genes for Brassica species genetic manipulation.
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Shirazi Z, Samavat S, Nezamivand Chegini M, Mohammadi Y, Banaei-Asl F. Identification and characterization of Metal Tolerance Protein (MTP) family in Glycyrrhiza uralensis. Biologia (Bratisl) 2021. [DOI: 10.1007/s11756-021-00880-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Mitra I, Huang B, Mousavi N, Ma N, Lamkin M, Yanicky R, Shleizer-Burko S, Lohmueller KE, Gymrek M. Patterns of de novo tandem repeat mutations and their role in autism. Nature 2021; 589:246-250. [PMID: 33442040 PMCID: PMC7810352 DOI: 10.1038/s41586-020-03078-7] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 11/23/2020] [Indexed: 12/19/2022]
Abstract
Autism Spectrum Disorder (ASD) is an early onset developmental disorder characterized by deficits in communication and social interaction and restrictive or repetitive behaviors1,2. Family studies demonstrate that ASD has a significant genetic basis with contributions both from inherited and de novo variants3,4. It has been estimated that de novo mutations may contribute to 30% of all simplex cases, in which only a single child is affected per family5. Tandem repeats (TRs), defined here as 1-20bp sequences repeated consecutively, comprise one of the largest sources of de novo mutations in humans6. TR expansions are implicated in dozens of neurological and psychiatric disorders7. Yet, de novo TR mutations have not been characterized on a genome-wide scale, and their contribution to ASD remains unexplored. We develop novel bioinformatics methods for identifying and prioritizing de novo TR mutations from sequencing data and then perform a genome-wide characterization of de novo TR mutations in ASD-affected probands and unaffected siblings. Compared to recent work on TRs in ASD8, we explicitly infer mutation events and their precise changes in repeat number, and primarily focus on more prevalent stepwise copy number changes rather than large expansions. Our results demonstrate a significant genome-wide excess of TR mutations in ASD probands. Mutations in probands tend to be larger, enriched in fetal brain regulatory regions, and predicted to be more evolutionarily deleterious. Overall, our results highlight the importance of considering repeat variants in future studies of de novo mutations.
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Affiliation(s)
- Ileena Mitra
- Bioinformatics and Systems Biology Program, University of California San Diego, La Jolla, CA, USA
| | - Bonnie Huang
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Nima Mousavi
- Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, CA, USA
| | - Nichole Ma
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Michael Lamkin
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Richard Yanicky
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | | | - Kirk E Lohmueller
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, CA, USA. .,Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA.
| | - Melissa Gymrek
- Department of Medicine, University of California San Diego, La Jolla, CA, USA. .,Department of Computer Science and Engineering, University of California San Diego, La Jolla, CA, USA.
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Albujja MH, Vasudevan R, Alghamdi S, Pei CP, Bin Mohd Ghani KA, Ranneh Y, Ismail PB. A review of studies examining the association between genetic biomarkers (short tandem repeats and single-nucleotide polymorphisms) and risk of prostate cancer: the need for valid predictive biomarkers. Prostate Int 2020; 8:135-145. [PMID: 33425790 PMCID: PMC7767939 DOI: 10.1016/j.prnil.2019.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/22/2019] [Accepted: 11/08/2019] [Indexed: 01/22/2023] Open
Abstract
Prostate cancer (PCa) is a challenging polygenic disease because the genes that cause PCa remain largely elusive and are affected by several causal factors. Consequently, research continuously strives to identify a genetic marker which could be used as an indicator to predict the most vulnerable (i.e., predisposed) segments of the population to the disease or for the gene which may be directly responsible for PCa. To enhance the genetic etiology of PCa, this research sought to discover the key studies conducted in this field using data from the main journal publication search engines, as it was hoped that this could shed light on the main research findings from these studies, which in turn could assist in determining these genes or markers. From the research highlighted, the studies primarily used two kinds of markers: short tandem repeats or single-nucleotide polymorphisms. These markers were found to be quite prevalent in all the chromosomes within the research carried out. It also became apparent that the studies differed in both quantity and quality, as well as being conducted in a variety of societies. Links were also determined between the degree and strength of the relationship between these markers and the occurrence of the disease. From the studies identified, most recommended a larger and more diverse survey for the parameters which had not been studied before, as well as an increase in the size of the community (i.e., the population) being studied. This is an indication that work in this field is far from complete, and thus, current research remains committed toward finding genetic markers that can be used clinically for the diagnosis and screening of patients with PCa.
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Affiliation(s)
- Mohammed H. Albujja
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor Malaysia
- Department of Forensic Sciences, Faculty of Criminal Justice, Naif Arab University of Security Sciences, Riyadh, Saudi Arabia
| | - Ramachandran Vasudevan
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor Malaysia
- Malaysian Research Institute on Ageing (MYAGEING), Malaysia
| | - Saleh Alghamdi
- Research Center, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Chong P. Pei
- School of Biosciences, Faculty of Health & Medical Sciences, Taylors University, Malaysia
| | - Khairul A. Bin Mohd Ghani
- Department of Surgery, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor Malaysia
| | - Yazan Ranneh
- Department of Nutrition and Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor Malaysia
| | - Patimah B. Ismail
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor Malaysia
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Hajiahmadi Z, Abedi A, Wei H, Sun W, Ruan H, Zhuge Q, Movahedi A. Identification, evolution, expression, and docking studies of fatty acid desaturase genes in wheat (Triticum aestivum L.). BMC Genomics 2020; 21:778. [PMID: 33167859 PMCID: PMC7653692 DOI: 10.1186/s12864-020-07199-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 10/27/2020] [Indexed: 12/28/2022] Open
Abstract
Backgrounds Fatty acid desaturases (FADs) introduce a double bond into the fatty acids acyl chain resulting in unsaturated fatty acids that have essential roles in plant development and response to biotic and abiotic stresses. Wheat germ oil, one of the important by-products of wheat, can be a good alternative for edible oils with clinical advantages due to the high amount of unsaturated fatty acids. Therefore, we performed a genome-wide analysis of the wheat FAD gene family (TaFADs). Results 68 FAD genes were identified from the wheat genome. Based on the phylogenetic analysis, wheat FADs clustered into five subfamilies, including FAB2, FAD2/FAD6, FAD4, DES/SLD, and FAD3/FAD7/FAD8. The TaFADs were distributed on chromosomes 2A-7B with 0 to 10 introns. The Ka/Ks ratio was less than one for most of the duplicated pair genes revealed that the function of the genes had been maintained during the evolution. Several cis-acting elements related to hormones and stresses in the TaFADs promoters indicated the role of these genes in plant development and responses to environmental stresses. Likewise, 72 SSRs and 91 miRNAs in 36 and 47 TaFADs have been identified. According to RNA-seq data analysis, the highest expression in all developmental stages and tissues was related to TaFAB2.5, TaFAB2.12, TaFAB2.15, TaFAB2.17, TaFAB2.20, TaFAD2.1, TaFAD2.6, and TaFAD2.8 genes while the highest expression in response to temperature stress was related to TaFAD2.6, TaFAD2.8, TaFAB2.15, TaFAB2.17, and TaFAB2.20. Furthermore, docking simulations revealed several residues in the active site of TaFAD2.6 and TaFAD2.8 in close contact with the docked oleic acid that could be useful in future site-directed mutagenesis studies to increase the catalytic efficiency of them and subsequently improve agronomic quality and tolerance of wheat against environmental stresses. Conclusions This study provides comprehensive information that can lead to the detection of candidate genes for wheat genetic modification. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-020-07199-1.
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Affiliation(s)
- Zahra Hajiahmadi
- Department of Agricultural Biotechnology, Faculty of Agricultural Sciences, University of Guilan, Rasht, 4199613776, Iran
| | - Amin Abedi
- Department of Agricultural Biotechnology, Faculty of Agricultural Sciences, University of Guilan, Rasht, 4199613776, Iran
| | - Hui Wei
- Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing, 210037, China
| | - Weibo Sun
- Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing, 210037, China
| | - Honghua Ruan
- Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing, 210037, China
| | - Qiang Zhuge
- Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing, 210037, China
| | - Ali Movahedi
- Co-Innovation Center for Sustainable Forestry in Southern China, Key Laboratory of Forest Genetics & Biotechnology, Ministry of Education, Nanjing Forestry University, Nanjing, 210037, China.
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Eshkiki EM, Hajiahmadi Z, Abedi A, Kordrostami M, Jacquard C. In Silico Analyses of Autophagy-Related Genes in Rapeseed ( Brassica napus L.) under Different Abiotic Stresses and in Various Tissues. PLANTS 2020; 9:plants9101393. [PMID: 33092180 PMCID: PMC7594038 DOI: 10.3390/plants9101393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 12/21/2022]
Abstract
The autophagy-related genes (ATGs) play important roles in plant growth and response to environmental stresses. Brassica napus (B. napus) is among the most important oilseed crops, but ATGs are largely unknown in this species. Therefore, a genome-wide analysis of the B. napus ATG gene family (BnATGs) was performed. One hundred and twenty-seven ATGs were determined due to the B. napus genome, which belongs to 20 main groups. Segmental duplication occurred more than the tandem duplication in BnATGs. Ka/Ks for the most duplicated pair genes were less than one, which indicated that the negative selection occurred to maintain their function during the evolution of B. napus plants. Based on the results, BnATGs are involved in various developmental processes and respond to biotic and abiotic stresses. One hundred and seven miRNA molecules are involved in the post-transcriptional regulation of 41 BnATGs. In general, 127 simple sequence repeat marker (SSR) loci were also detected in BnATGs. Based on the RNA-seq data, the highest expression in root and silique was related to BnVTI12e, while in shoot and seed, it was BnATG8p. The expression patterns of the most BnATGs were significantly up-regulated or down-regulated responding to dehydration, salinity, abscisic acid, and cold. This research provides information that can detect candidate genes for genetic manipulation in B. napus.
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Affiliation(s)
- Elham Mehri Eshkiki
- Department of Agricultural Biotechnology, Payame Noor University (PNU), Tehran P.O. Box 19395-4697, Iran;
| | - Zahra Hajiahmadi
- Department of Biotechnology, Faculty of Agricultural Sciences, University of Guilan, Rasht P.O. Box 41635-1314, Iran; (Z.H.); (A.A.)
| | - Amin Abedi
- Department of Biotechnology, Faculty of Agricultural Sciences, University of Guilan, Rasht P.O. Box 41635-1314, Iran; (Z.H.); (A.A.)
| | - Mojtaba Kordrostami
- Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute (NSTRI), Karaj P.O. Box 31485498, Iran;
| | - Cédric Jacquard
- Resistance Induction and Bioprotection of Plants Unit (RIBP)—EA4707, SFR Condorcet FR CNRS 3417, University of Reims Champagne-Ardenne, Moulin de la Housse, CEDEX 2, BP 1039, 51687 Reims, France
- Correspondence: ; Tel.: +33-3-26-91-34-36
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Linløkken AN, Garlie S, Johansen W, Wilson RC. Assessing Evolutionary Significant Units (ESU) of the Endangered Freshwater Pearl Mussel ( Margaritifera margaritifera) in Southeast Norway on the Basis of Genetic Analysis. Genes (Basel) 2020; 11:E1061. [PMID: 32911821 PMCID: PMC7565849 DOI: 10.3390/genes11091061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/29/2020] [Accepted: 09/04/2020] [Indexed: 11/16/2022] Open
Abstract
A total of 312 specimens of freshwater pearl mussel (Margaritifera margaritifera) were sampled from 11 populations, located in four different river systems in Southeast Norway, and analyzed for 11 simple sequence repeat (SSR) (microsatellite) markers. All study populations have landlocked brown trout (Salmo trutta) as the only possible host. Several populations had experienced recruitment failure, probably due to low pH (about 6.0) and calcium concentration. STRUCTURE clustering analysis revealed two genetic clusters, of which one cluster occurred mainly in the western river systems, and totally dominated in one population (Fallselva (A-FAL)) that had higher genetic diversity than the others. Cluster 2 completely dominated in the populations of the eastern river systems, and all of them had low genetic diversity. Bottleneck events were indicated in all populations and the inbreeding coefficient FIS was significant in all populations, except for the southernmost population (Sørkedalselva (B-SØR)), which was the only population with genotypes in Hardy-Weinberg equilibrium. FIS were especially high in the populations of the eastern river systems, and maximum shell length was negatively correlated to FIS. If artificially breeding and stocking should become necessary for future preservation, it should be based on single populations; alternatively, the eastern populations should be based on cross-breeding of populations within the cluster to increase their genetic diversity.
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Affiliation(s)
- Arne N. Linløkken
- Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, N-2418 Elverum, Norway; (S.G.); (W.J.); (R.C.W.)
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E GX, Chen LP, Zhou DK, Yang BG, Zhang JH, Zhao YJ, Hong QH, Ma YH, Chu MX, Zhang LP, Basang WD, Zhu YB, Han YG, Na RS, Zeng Y, Zhao ZQ, Huang YF, Han JL. Evolutionary relationship and population structure of domestic Bovidae animals based on MHC-linked and neutral autosomal microsatellite markers. Mol Immunol 2020; 124:83-90. [PMID: 32544655 DOI: 10.1016/j.molimm.2020.05.005] [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: 12/30/2019] [Revised: 04/21/2020] [Accepted: 05/07/2020] [Indexed: 11/26/2022]
Abstract
Major histocompatibility complex (MHC) genes are critical for disease resistance or susceptibility responsible for host-pathogen interactions determined mainly by extensive polymorphisms in the MHC genes. Here, we examined the diversity and phylogenetic pattern of MHC haplotypes reconstructed using three MHC-linked microsatellite markers in 55 populations of five Bovidae species and compared them with those based on neutral autosomal microsatellite markers (NAMs). Three-hundred-and-forty MHC haplotypes were identified in 1453 Bovidae individuals, suggesting significantly higher polymorphism and heterozygosity compared with those based on NAMs. The ambitious boundaries in population differentiation (phylogenetic network, pairwise FST and STRUCTURE analyses) within and between species assessed using the MHC haplotypes were different from those revealed by NAMs associated closely with speciation, geographical distribution, domestication and management histories. In addition, the mean FST was significantly correlated negatively with the number of observed alleles (NA), observed (HO) and expected (HE) heterozygosity and polymorphism information content (PIC) (P < 0.05) in the MHC haplotype dataset while there was no correction of the mean FST estimates (P> 0.05) between the MHC haplotype and NAMs datasets. Analysis of molecular variance (AMOVA) revealed a lower percentage of total variance (PTV) between species/groups based on the MHC-linked microsatellites than NAMs. Therefore, it was inferred that individuals within populations accumulated as many MHC variants as possible to increase their heterozygosity and thus the survival rate of their affiliated populations and species, which eventually reduced population differentiation and thereby complicated their classification and phylogenetic relationship inference. In summary, host-pathogen coevolution and heterozygote advantage, rather than demographic history, act as key driving forces shaping the MHC diversity within the populations and determining the interspecific MHC diversity.
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Affiliation(s)
- Guang-Xin E
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Li-Peng Chen
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Dong-Ke Zhou
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Bai-Gao Yang
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Jia-Hua Zhang
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Yong-Ju Zhao
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Qiong-Hua Hong
- Yunnan Animal Science and Veterinary Institute, Kunming 650224, China
| | - Yue-Hui Ma
- Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Ming-Xing Chu
- Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Lu-Pei Zhang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Wang-Dui Basang
- State Key Laboratory of Barley and Yak Germplasm Resources and Genetic Improvement (Tibet Academy of Agricultural and Animal Husbandry Science (TAAAS)), Lhasa 850002, China
| | - Yan-Bin Zhu
- State Key Laboratory of Barley and Yak Germplasm Resources and Genetic Improvement (Tibet Academy of Agricultural and Animal Husbandry Science (TAAAS)), Lhasa 850002, China
| | - Yan-Guo Han
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Ri-Su Na
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Yan Zeng
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Zhong-Quan Zhao
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China
| | - Yong-Fu Huang
- College of Animal Science and Technology, Chongqing Key Laboratory of Forage & Herbivores, Chongqing Engineering Research Centre for Herbivore Resource Protection and Utilization, Southwest University, Chongqing 400716, China.
| | - Jian-Lin Han
- CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China; Livestock Genetics Program, International Livestock Research Institute (ILRI), Nairobi 00100, Kenya.
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15
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Kanzana G, Zhang Y, Ma T, Liu W, Wu F, Yan Q, Min X, Yan Z, Muvunyi BP, Li J, Zhang Z, Zhao Y, Zhang J. Genome-wide development of miRNA-based SSR markers in Cleistogenes songorica and analysis of their transferability to Gramineae/non-Gramineae species. J Appl Genet 2020; 61:367-377. [PMID: 32507975 DOI: 10.1007/s13353-020-00561-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 04/28/2020] [Accepted: 05/07/2020] [Indexed: 11/24/2022]
Abstract
Simple sequence repeat (SSR) markers are commonly used for many genetic applications, such as map construction, fingerprinting, and genetic diversity analyses, due to their high reproducibility, polymorphism, and abundance. Endogenous miRNAs play essential roles in plant development and gene expression under diverse biotic and abiotic stress conditions. In the present study, we predicted 110 miRNA-SSR primer pairs from 287 precursor miRNAs. Among 110 primer pairs, 85 were successfully amplified and examined for transferability to other Gramineae and non-Gramineae species. The results showed that all 82 primer pairs yielded unambiguous and strong amplification, and across the 23 studied Cleistogenes accessions, a total of 385 alleles were polymorphic. The number of alleles produced per primer varied from 3 to 11, with an average of 4.69 per locus. The expected heterozygosity (He) ranged from 0.44 to 0.88, with an average of 0.74 per locus, and the PIC (Polymorphism Information Content) values ranged from 0.34 to 0.87, with an average of 0.69 per locus. Furthermore, 1422 miRNA target genes were predicted and analyzed using the GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) databases. In conclusion, the results showed that an miRNA-based microsatellite marker system can be applicable for genetic diversity and marker-assisted breeding studies.
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Affiliation(s)
- Gisele Kanzana
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Yufei Zhang
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Tiantian Ma
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Wenxian Liu
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Fan Wu
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Qi Yan
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Xueyang Min
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Zhuanzhuan Yan
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Blaise Pascal Muvunyi
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Jie Li
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Zhengshe Zhang
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Yufeng Zhao
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China
| | - Jiyu Zhang
- State Key Laboratory of Grassland Agro-Ecosystems, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730020, People's Republic of China.
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16
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Daemi-Saeidabad M, Shojaeiyan A, Vivian-Smith A, Stenøien HK, Falahati-Anbaran M. The taxonomic significance of ddRADseq based microsatellite markers in the closely related species of Heracleum (Apiaceae). PLoS One 2020; 15:e0232471. [PMID: 32379780 PMCID: PMC7205262 DOI: 10.1371/journal.pone.0232471] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 04/15/2020] [Indexed: 11/28/2022] Open
Abstract
Many studies on Heracleum have shown poor correspondence between observed molecular clusters and established taxonomic classification amongst closely related species. This might reflect both unresolved taxonomy but perhaps also a lack of good genetic markers. This lack of appropriate and cost effective species-specific genetic markers hinders a resolved relationship for the species complex, and this in turn causes profound management challenges for a genus that contains both endemic species, with important ecological roles, and species with an invasive potential. Microsatellites are traditionally considered markers of choice for comprehensive, yet inexpensive, analyses of genetic variation, including examination of population structure, species identity, linkage map construction and cryptic speciation. In this study, we have used double digest restriction site associated DNA sequencing (ddRADseq) to develop microsatellite markers in Heracleum rechingeri. Genomic DNA from three individuals were digested with Sbf1 and Nde1 and size selected for library construction. The size-selected fragments were sequenced on an Ion Torrent sequencer and a total of 54 microsatellite sequences were bioinformatically confirmed. Twenty five loci were then tested for amplification, resulting in 19 of these being successfully amplified across eight species, comprising both the so-called thick-stemmed species (H. persicum, H. rechingeri, H. gorganicum and H. lasiopetalum), and thin-stemmed species (H. anisactis, H. pastinasifolium and H. transcaucasicum). Both Bayesian and distance-based clustering, and principal coordinate analyses clearly separated these into two groups. Surprisingly, three H. pastinacifolium populations were not separated from populations of the morphologically similar endemic species, H. anisactis, suggesting lack of genetic differentiation. Likewise, high genetic similarity was found between H. persicum and H. rechingeri populations, questioning taxonomic separation at the species level between these taxa. Further analyses are needed to re-evaluate the taxonomic significance of observed morphological variability currently applied to distinguish these sister taxa. Nevertheless, our results represent progress in the effort to develop cost-efficient molecular tools for species discrimination in this genus.
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Affiliation(s)
- Mehdi Daemi-Saeidabad
- Department of Plant Sciences, School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Abdolali Shojaeiyan
- Department of Horticultural Science, Faculty of Agriculture, Tarbiat Modares University (TMU), Tehran, Iran
| | - Adam Vivian-Smith
- Department of Forest Genetics and Biodiversity, Norwegian Institute for Bioeconomy Research, Ås, Norway
| | - Hans K. Stenøien
- NTNU University Museum, Norwegian University of Science and Technology, Trondheim, Norway
| | - Mohsen Falahati-Anbaran
- Department of Plant Sciences, School of Biology, College of Science, University of Tehran, Tehran, Iran
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17
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Ho EKH, Macrae F, Latta LC, Benner MJ, Sun C, Ebert D, Schaack S. Intraspecific Variation in Microsatellite Mutation Profiles in Daphnia magna. Mol Biol Evol 2020; 36:1942-1954. [PMID: 31077327 PMCID: PMC6934441 DOI: 10.1093/molbev/msz118] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Microsatellite loci (tandem repeats of short nucleotide motifs) are highly abundant in eukaryotic genomes and often used as genetic markers because they can exhibit variation both within and between populations. Although widely recognized for their mutability and utility, the mutation rates of microsatellites have only been empirically estimated in a few species, and have rarely been compared across genotypes and populations within a species. Here, we investigate the dynamics of microsatellite mutation over long- and short-time periods by quantifying the starting abundance and mutation rates for microsatellites for six different genotypes of Daphnia magna, an aquatic microcrustacean, collected from three populations (Finland, Germany, and Israel). Using whole-genome sequences of these six starting genotypes, descendent mutation accumulation (MA) lines, and large population controls (non-MA lines), we find each genotype exhibits a distinctive initial microsatellite profile which clusters according to the population-of-origin. During the period of MA, we observe motif-specific, highly variable, and rapid microsatellite mutation rates across genotypes of D. magna, the average of which is order of magnitude greater than the recently reported rate observed in a single genotype of the congener, Daphnia pulex. In our experiment, genotypes with more microsatellites starting out exhibit greater losses and those with fewer microsatellites starting out exhibit greater gains—a context-dependent mutation bias that has not been reported previously. We discuss how genotype-specific mutation rates and spectra, in conjunction with evolutionary forces, can shape both the differential accumulation of repeat content in the genome and the evolution of mutation rates.
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Affiliation(s)
- Eddie K H Ho
- Department of Biology, Reed College, Portland, OR
| | | | - Leigh C Latta
- Department of Biology, Reed College, Portland, OR
- Division of Natural Sciences and Mathematics, Lewis-Clark State College, Lewiston, ID
| | | | - Cheng Sun
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Dieter Ebert
- Department of Environmental Sciences, Zoology, University of Basel, Basel, Switzerland
| | - Sarah Schaack
- Department of Biology, Reed College, Portland, OR
- Corresponding author: E-mail:
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18
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Kinney N, Kang L, Eckstrand L, Pulenthiran A, Samuel P, Anandakrishnan R, Varghese RT, Michalak P, Garner HR. Abundance of ethnically biased microsatellites in human gene regions. PLoS One 2019; 14:e0225216. [PMID: 31830051 PMCID: PMC6907796 DOI: 10.1371/journal.pone.0225216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/29/2019] [Indexed: 12/16/2022] Open
Abstract
Microsatellites-a type of short tandem repeat (STR)-have been used for decades as putatively neutral markers to study the genetic structure of diverse human populations. However, recent studies have demonstrated that some microsatellites contribute to gene expression, cis heritability, and phenotype. As a corollary, some microsatellites may contribute to differential gene expression and RNA/protein structure stability in distinct human populations. To test this hypothesis, we investigate genotype frequencies, functional relevance, and adaptive potential of microsatellites in five super-populations (ethnicities) drawn from the 1000 Genomes Project. We discover 3,984 ethnically-biased microsatellite loci (EBML); for each EBML at least one ethnicity has genotype frequencies statistically different from the remaining four. South Asian, East Asian, European, and American EBML show significant overlap; on the contrary, the set of African EBML is mostly unique. We cross-reference the 3,984 EBML with 2,060 previously identified expression STRs (eSTRs); repeats known to affect gene expression (64 total) are over-represented. The most significant pathway enrichments are those associated with the matrisome: a broad collection of genes encoding the extracellular matrix and its associated proteins. At least 14 of the EBML have established links to human disease. Analysis of the 3,984 EBML with respect to known selective sweep regions in the genome shows that allelic variation in some of them is likely associated with adaptive evolution.
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Affiliation(s)
- Nick Kinney
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
- Gibbs Cancer Center & Research Institute, Spartanburg, SC, United States of America
| | - Lin Kang
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
- Gibbs Cancer Center & Research Institute, Spartanburg, SC, United States of America
| | - Laurel Eckstrand
- Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, United States of America
| | - Arichanah Pulenthiran
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
| | - Peter Samuel
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
| | - Ramu Anandakrishnan
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
| | - Robin T. Varghese
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
| | - P. Michalak
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
- Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, United States of America
- Institute of Evolution, University of Haifa, Haifa, Israel
| | - Harold R. Garner
- Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States of America
- Gibbs Cancer Center & Research Institute, Spartanburg, SC, United States of America
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19
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Li D, Zhang H, Peng S, Pan S, Tan Z. Conserved microsatellites may contribute to stem-loop structures in 5', 3' terminals of Ebolavirus genomes. Biochem Biophys Res Commun 2019; 514:726-733. [PMID: 31078274 PMCID: PMC7092875 DOI: 10.1016/j.bbrc.2019.04.192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 04/25/2019] [Accepted: 04/28/2019] [Indexed: 12/12/2022]
Abstract
Microsatellites (SSRs) are ubiquitous in coding and non-coding regions of the Ebolavirus genomes. We synthetically analyzed the microsatellites in whole-genome and terminal regions of 219 Ebolavirus genomes from five species. The Ebolavirus sequences were observed with small intraspecies variations and large interspecific variations, especially in the terminal non-coding regions. Only five conserved microsatellites were detected in the complete genomes, and four of them which well base-paired to help forming conserved stem-loop structures mainly appeared in the terminal non-coding regions. These results suggest that the conserved microsatellites may be evolutionary selected to form conserved secondary structures in 5′, 3′ terminals of Ebolavirus genomes. It may help to understand the biological significance of microsatellites in Ebolavirus and also other virus genomes. Conserved microsatellites mainly occurred in 5′, 3′ terminal non-coding regions. Conserved microsatellites may contribute to conserved stem-loop structures. Conserved microsatellites might be preserved under greater evolutionary pressure.
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Affiliation(s)
- Douyue Li
- Bioinformatics Center, College of Biology, Hunan University, Changsha, China
| | - Hongxi Zhang
- Bioinformatics Center, College of Biology, Hunan University, Changsha, China
| | - Shan Peng
- Bioinformatics Center, College of Biology, Hunan University, Changsha, China
| | - Saichao Pan
- Bioinformatics Center, College of Biology, Hunan University, Changsha, China
| | - Zhongyang Tan
- Bioinformatics Center, College of Biology, Hunan University, Changsha, China.
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20
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Taking Advantage of the Genomics Revolution for Monitoring and Conservation of Chondrichthyan Populations. DIVERSITY-BASEL 2019. [DOI: 10.3390/d11040049] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Chondrichthyes (sharks, rays, skates and chimaeras) are among the oldest extant predators and are vital to top-down regulation of oceanic ecosystems. They are an ecologically diverse group occupying a wide range of habitats and are thus, exploited by coastal, pelagic and deep-water fishing industries. Chondrichthyes are among the most data deficient vertebrate species groups making design and implementation of regulatory and conservation measures challenging. High-throughput sequencing technologies have significantly propelled ecological investigations and understanding of marine and terrestrial species’ populations, but there remains a paucity of NGS based research on chondrichthyan populations. We present a brief review of current methods to access genomic and metagenomic data from Chondrichthyes and discuss applications of these datasets to increase our understanding of chondrichthyan taxonomy, evolution, ecology and population structures. Last, we consider opportunities and challenges offered by genomic studies for conservation and management of chondrichthyan populations.
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21
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Herman JS, Stojak J, Paupério J, Jaarola M, Wójcik JM, Searle JB. Genetic variation in field voles ( Microtus agrestis) from the British Isles: selective sweeps or population bottlenecks? Biol J Linn Soc Lond 2019. [DOI: 10.1093/biolinnean/bly213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
| | - Joanna Stojak
- Mammal Research Institute of Polish Academy of Sciences, Białowieża, Poland
| | - Joana Paupério
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
| | - Maarit Jaarola
- Department of Clinical and Experimental Medicine, Linköping University, Sweden
| | - Jan M Wójcik
- Mammal Research Institute of Polish Academy of Sciences, Białowieża, Poland
| | - Jeremy B Searle
- Department of Ecology and Evolution, Cornell University, Ithaca, NY, USA
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22
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Comparative analysis on precise distribution-patterns of microsatellites in HIV-1 with differential statistical method. GENE REPORTS 2018. [DOI: 10.1016/j.genrep.2018.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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24
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Press MO, McCoy RC, Hall AN, Akey JM, Queitsch C. Massive variation of short tandem repeats with functional consequences across strains of Arabidopsis thaliana. Genome Res 2018; 28:1169-1178. [PMID: 29970452 PMCID: PMC6071631 DOI: 10.1101/gr.231753.117] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 06/26/2018] [Indexed: 11/24/2022]
Abstract
Short tandem repeat (STR) mutations may comprise more than half of the mutations in eukaryotic coding DNA, yet STR variation is rarely examined as a contributor to complex traits. We assessed this contribution across a collection of 96 strains of Arabidopsis thaliana, genotyping 2046 STR loci each, using highly parallel STR sequencing with molecular inversion probes. We found that 95% of examined STRs are polymorphic, with a median of six alleles per STR across these strains. STR expansions (large copy number increases) are found in most strains, several of which have evident functional effects. These include three of six intronic STR expansions we found to be associated with intron retention. Coding STRs were depleted of variation relative to noncoding STRs, and we detected a total of 56 coding STRs (11%) showing low variation consistent with the action of purifying selection. In contrast, some STRs show hypervariable patterns consistent with diversifying selection. Finally, we detected 133 novel STR-phenotype associations under stringent criteria, most of which could not be detected with SNPs alone, and validated some with follow-up experiments. Our results support the conclusion that STRs constitute a large, unascertained reservoir of functionally relevant genomic variation.
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Affiliation(s)
- Maximilian O Press
- Department of Genome Sciences, University of Washington, Seattle, Washington 98195, USA
| | - Rajiv C McCoy
- Department of Genome Sciences, University of Washington, Seattle, Washington 98195, USA
| | - Ashley N Hall
- Department of Genome Sciences, University of Washington, Seattle, Washington 98195, USA.,Molecular and Cellular Biology Program, University of Washington, Seattle, Washington 98195, USA
| | - Joshua M Akey
- Department of Genome Sciences, University of Washington, Seattle, Washington 98195, USA
| | - Christine Queitsch
- Department of Genome Sciences, University of Washington, Seattle, Washington 98195, USA
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25
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De-novo assembly and transcriptome analysis of Odontesthes argentinensis gill tissue, with development of single sequence repeat markers. GENE REPORTS 2018. [DOI: 10.1016/j.genrep.2018.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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26
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Tørresen OK, Brieuc MSO, Solbakken MH, Sørhus E, Nederbragt AJ, Jakobsen KS, Meier S, Edvardsen RB, Jentoft S. Genomic architecture of haddock (Melanogrammus aeglefinus) shows expansions of innate immune genes and short tandem repeats. BMC Genomics 2018; 19:240. [PMID: 29636006 PMCID: PMC5894186 DOI: 10.1186/s12864-018-4616-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 03/22/2018] [Indexed: 02/06/2023] Open
Abstract
Background Increased availability of genome assemblies for non-model organisms has resulted in invaluable biological and genomic insight into numerous vertebrates, including teleosts. Sequencing of the Atlantic cod (Gadus morhua) genome and the genomes of many of its relatives (Gadiformes) demonstrated a shared loss of the major histocompatibility complex (MHC) II genes 100 million years ago. An improved version of the Atlantic cod genome assembly shows an extreme density of tandem repeats compared to other vertebrate genome assemblies. Highly contiguous assemblies are therefore needed to further investigate the unusual immune system of the Gadiformes, and whether the high density of tandem repeats found in Atlantic cod is a shared trait in this group. Results Here, we have sequenced and assembled the genome of haddock (Melanogrammus aeglefinus) – a relative of Atlantic cod – using a combination of PacBio and Illumina reads. Comparative analyses reveal that the haddock genome contains an even higher density of tandem repeats outside and within protein coding sequences than Atlantic cod. Further, both species show an elevated number of tandem repeats in genes mainly involved in signal transduction compared to other teleosts. A characterization of the immune gene repertoire demonstrates a substantial expansion of MCHI in Atlantic cod compared to haddock. In contrast, the Toll-like receptors show a similar pattern of gene losses and expansions. For the NOD-like receptors (NLRs), another gene family associated with the innate immune system, we find a large expansion common to all teleosts, with possible lineage-specific expansions in zebrafish, stickleback and the codfishes. Conclusions The generation of a highly contiguous genome assembly of haddock revealed that the high density of short tandem repeats as well as expanded immune gene families is not unique to Atlantic cod – but possibly a feature common to all, or most, codfishes. A shared expansion of NLR genes in teleosts suggests that the NLRs have a more substantial role in the innate immunity of teleosts than other vertebrates. Moreover, we find that high copy number genes combined with variable genome assembly qualities may impede complete characterization of these genes, i.e. the number of NLRs in different teleost species might be underestimates. Electronic supplementary material The online version of this article (10.1186/s12864-018-4616-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ole K Tørresen
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway.
| | - Marine S O Brieuc
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Monica H Solbakken
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Elin Sørhus
- Institute of Marine Research, Bergen, Norway
| | - Alexander J Nederbragt
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway.,Biomedical Informatics Research Group, Department of Informatics, University of Oslo, Oslo, Norway
| | - Kjetill S Jakobsen
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | | | | | - Sissel Jentoft
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway.
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27
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Xu L, Haasl RJ, Sun J, Zhou Y, Bickhart DM, Li J, Song J, Sonstegard TS, Van Tassell CP, Lewin HA, Liu GE. Systematic Profiling of Short Tandem Repeats in the Cattle Genome. Genome Biol Evol 2018; 9:20-31. [PMID: 28172841 PMCID: PMC5381564 DOI: 10.1093/gbe/evw256] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2016] [Indexed: 12/13/2022] Open
Abstract
Short tandem repeats (STRs), or microsatellites, are genetic variants with repetitive 2–6 base pair motifs in many mammalian genomes. Using high-throughput sequencing and experimental validations, we systematically profiled STRs in five Holsteins. We identified a total of 60,106 microsatellites and generated the first high-resolution STR map, representing a substantial pool of polymorphism in dairy cattle. We observed significant STRs overlap with functional genes and quantitative trait loci (QTL). We performed evolutionary and population genetic analyses using over 20,000 common dinucleotide STRs. Besides corroborating the well-established positive correlation between allele size and variance in allele size, these analyses also identified dozens of outlier STRs based on two anomalous relationships that counter expected characteristics of neutral evolution. And one STR locus overlaps with a significant region of a summary statistic designed to detect STR-related selection. Additionally, our results showed that only 57.1% of STRs located within SNP-based linkage disequilibrium (LD) blocks whereas the other 42.9% were out of blocks. Therefore, a substantial number of STRs are not tagged by SNPs in the cattle genome, likely due to STR's distinct mutation mechanism and elevated polymorphism. This study provides the foundation for future STR-based studies of cattle genome evolution and selection.
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Affiliation(s)
- Lingyang Xu
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, Beltsville, MD.,Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China.,Department of Animal and Avian Sciences, University of Maryland, College Park, MD
| | - Ryan J Haasl
- Department of Biology, University of Wisconsin - Platteville, WI
| | - Jiajie Sun
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Yang Zhou
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, Beltsville, MD.,College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shannxi, China
| | - Derek M Bickhart
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, Beltsville, MD
| | - Junya Li
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiuzhou Song
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD
| | - Tad S Sonstegard
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, Beltsville, MD
| | - Curtis P Van Tassell
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, Beltsville, MD
| | - Harris A Lewin
- Department of Evolution and Ecology, University of California, Davis, CA
| | - George E Liu
- Animal Genomics and Improvement Laboratory, Agricultural Research Service, Beltsville, MD
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28
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Gymrek M, Willems T, Reich D, Erlich Y. Interpreting short tandem repeat variations in humans using mutational constraint. Nat Genet 2017; 49:1495-1501. [PMID: 28892063 PMCID: PMC5679271 DOI: 10.1038/ng.3952] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 08/14/2017] [Indexed: 12/19/2022]
Abstract
Identifying regions of the genome that are depleted of mutations can distinguish potentially deleterious variants. Short tandem repeats (STRs), also known as microsatellites, are among the largest contributors of de novo mutations in humans. However, per-locus studies of STR mutations have been limited to highly ascertained panels of several dozen loci. Here we harnessed bioinformatics tools and a novel analytical framework to estimate mutation parameters for each STR in the human genome by correlating STR genotypes with local sequence heterozygosity. We applied our method to obtain robust estimates of the impact of local sequence features on mutation parameters and used these estimates to create a framework for measuring constraint at STRs by comparing observed versus expected mutation rates. Constraint scores identified known pathogenic variants with early-onset effects. Our metric will provide a valuable tool for prioritizing pathogenic STRs in medical genetics studies.
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Affiliation(s)
- Melissa Gymrek
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- New York Genome Center, New York, NY, USA
- Department of Medicine, University of California San Diego, La Jolla, CA USA
- Department of Computer Science and Engineering, University of California San Diego, La Jolla, CA USA
| | - Thomas Willems
- New York Genome Center, New York, NY, USA
- Computational and Systems Biology Program, Massachusetts Institute of Technology, Cambridge, MA USA
| | - David Reich
- Department of Genetics, Harvard Medical School, Boston, MA USA
- Howard Hughes Medical Institute, Harvard Medical School, Boston, MA USA
| | - Yaniv Erlich
- New York Genome Center, New York, NY, USA
- Department of Computer Science, Fu Foundation School of Engineering, Columbia University, New York, NY, USA
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29
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Pieper KE, Dyer KA. Occasional recombination of a selfish X-chromosome may permit its persistence at high frequencies in the wild. J Evol Biol 2016; 29:2229-2241. [PMID: 27423061 DOI: 10.1111/jeb.12948] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 07/12/2016] [Accepted: 07/13/2016] [Indexed: 01/07/2023]
Abstract
The sex-ratio X-chromosome (SR) is a selfish chromosome that promotes its own transmission to the next generation by destroying Y-bearing sperm in the testes of carrier males. In some natural populations of the fly Drosophila neotestacea, up to 30% of the X-chromosomes are SR chromosomes. To investigate the molecular evolutionary history and consequences of SR, we sequenced SR and standard (ST) males at 11 X-linked loci that span the ST X-chromosome and at seven arbitrarily chosen autosomal loci from a sample of D. neotestacea males from throughout the species range. We found that the evolutionary relationship between ST and SR varies among individual markers, but genetic differentiation between SR and ST is chromosome-wide and likely due to large chromosomal inversions that suppress recombination. However, SR does not consist of a single multilocus haplotype: we find evidence for gene flow between ST and SR at every locus assayed. Furthermore, we do not find long-distance linkage disequilibrium within SR chromosomes, suggesting that recombination occurs in females homozygous for SR. Finally, polymorphism on SR is reduced compared to that on ST, and loci displaying signatures of selection on ST do not show similar patterns on SR. Thus, even if selection is less effective on SR, our results suggest that gene flow with ST and recombination between SR chromosomes may prevent the accumulation of deleterious mutations and allow its long-term persistence at relatively high frequencies.
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Affiliation(s)
- K E Pieper
- Department of Genetics, University of Georgia, Athens, GA, USA.
| | - K A Dyer
- Department of Genetics, University of Georgia, Athens, GA, USA
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30
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Shimada MK, Sanbonmatsu R, Yamaguchi-Kabata Y, Yamasaki C, Suzuki Y, Chakraborty R, Gojobori T, Imanishi T. Selection pressure on human STR loci and its relevance in repeat expansion disease. Mol Genet Genomics 2016; 291:1851-69. [PMID: 27290643 DOI: 10.1007/s00438-016-1219-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Accepted: 05/21/2016] [Indexed: 12/30/2022]
Abstract
Short Tandem Repeats (STRs) comprise repeats of one to several base pairs. Because of the high mutability due to strand slippage during DNA synthesis, rapid evolutionary change in the number of repeating units directly shapes the range of repeat-number variation according to selection pressure. However, the remaining questions include: Why are STRs causing repeat expansion diseases maintained in the human population; and why are these limited to neurodegenerative diseases? By evaluating the genome-wide selection pressure on STRs using the database we constructed, we identified two different patterns of relationship in repeat-number polymorphisms between DNA and amino-acid sequences, although both patterns are evolutionary consequences of avoiding the formation of harmful long STRs. First, a mixture of degenerate codons is represented in poly-proline (poly-P) repeats. Second, long poly-glutamine (poly-Q) repeats are favored at the protein level; however, at the DNA level, STRs encoding long poly-Qs are frequently divided by synonymous SNPs. Furthermore, significant enrichments of apoptosis and neurodevelopment were biological processes found specifically in genes encoding poly-Qs with repeat polymorphism. This suggests the existence of a specific molecular function for polymorphic and/or long poly-Q stretches. Given that the poly-Qs causing expansion diseases were longer than other poly-Qs, even in healthy subjects, our results indicate that the evolutionary benefits of long and/or polymorphic poly-Q stretches outweigh the risks of long CAG repeats predisposing to pathological hyper-expansions. Molecular pathways in neurodevelopment requiring long and polymorphic poly-Q stretches may provide a clue to understanding why poly-Q expansion diseases are limited to neurodegenerative diseases.
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Affiliation(s)
- Makoto K Shimada
- Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi, 470-1192, Japan. .,National Institute of Advanced Industrial Science and Technology, 2-3-26 Aomi Koto-ku, Tokyo, 135-0064, Japan. .,Japan Biological Informatics Consortium, 10F TIME24 Building, 2-4-32 Aomi, Koto-ku, Tokyo, 135-8073, Japan.
| | - Ryoko Sanbonmatsu
- Japan Biological Informatics Consortium, 10F TIME24 Building, 2-4-32 Aomi, Koto-ku, Tokyo, 135-8073, Japan
| | - Yumi Yamaguchi-Kabata
- National Institute of Advanced Industrial Science and Technology, 2-3-26 Aomi Koto-ku, Tokyo, 135-0064, Japan.,Tohoku Medical Megabank Organization, Tohoku University, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8573, Japan
| | - Chisato Yamasaki
- National Institute of Advanced Industrial Science and Technology, 2-3-26 Aomi Koto-ku, Tokyo, 135-0064, Japan.,Japan Biological Informatics Consortium, 10F TIME24 Building, 2-4-32 Aomi, Koto-ku, Tokyo, 135-8073, Japan
| | - Yoshiyuki Suzuki
- Graduate School of Natural Sciences, Nagoya City University, 1 Yamanohata, Mizuho-cho, Mizuho-ku, Nagoya, Aichi, 467-8501, Japan
| | - Ranajit Chakraborty
- Health Science Center, University of North Texas, 3500 Camp Bowie Blvd., Fort Worth, TX, 76107, USA
| | - Takashi Gojobori
- National Institute of Advanced Industrial Science and Technology, 2-3-26 Aomi Koto-ku, Tokyo, 135-0064, Japan.,Computational Bioscience Research Center, King Abdullah University of Science and Technology, Ibn Al-Haytham Building (West), Thuwal, 23955-6900, Kingdom of Saudi Arabia
| | - Tadashi Imanishi
- National Institute of Advanced Industrial Science and Technology, 2-3-26 Aomi Koto-ku, Tokyo, 135-0064, Japan.,Department of Molecular Life Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
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31
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Gonthier P, Sillo F, Lagostina E, Roccotelli A, Cacciola OS, Stenlid J, Garbelotto M. Selection processes in simple sequence repeats suggest a correlation with their genomic location: insights from a fungal model system. BMC Genomics 2015; 16:1107. [PMID: 26714466 PMCID: PMC4696308 DOI: 10.1186/s12864-015-2274-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 12/03/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Adaptive processes shape the evolution of genomes and the diverse functions of different genomic regions are likely to have an impact on the trajectory and outcome of this evolution. The main underlying hypothesis of this study is that the evolution of Simple Sequence Repeats (SSRs) is correlated with the evolution of the genomic region in which they are located, resulting in differences of motif size, number of repeats, and levels of polymorphisms. These differences should be clearly detectable when analyzing the frequency and type of SSRs within the genome of a species, when studying populations within a species, and when comparing closely related sister taxa. By coupling a genome-wide SSR survey in the genome of the plant pathogenic fungus Heterobasidion irregulare with an analysis of intra- and interspecific variability of 39 SSR markers in five populations of the two sibling species H. irregulare and H. annosum, we investigated mechanisms of evolution of SSRs. RESULTS Results showed a clear dominance of trirepeats and a selection against other repeat number, i.e. di- and tetranucleotides, both in regions inside Open Reading Frames (ORFs) and upstream 5' untranslated region (5'UTR). Locus per locus AMOVA showed SSRs both inside ORFs and upstream 5'UTR were more conserved within species compared to SSRs in other genomic regions, suggesting their evolution is constrained by the functions of the regions they are in. Principal coordinates analysis (PCoA) indicated that even if SSRs inside ORFs were less polymorphic than those in intergenic regions, they were more powerful in differentiating species. These findings indicate SSRs evolution undergoes a directional selection pressure comparable to that of the ORFs they interrupt and to that of regions involved in regulatory functions. CONCLUSIONS Our work linked the variation and the type of SSRs with regions upstream 5'UTR, putatively harbouring regulatory elements, and shows that the evolution of SSRs might be affected by their location in the genome. Additionally, this study provides a first glimpse on a possible molecular basis for fast adaptation to the environment mediated by SSRs.
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Affiliation(s)
- Paolo Gonthier
- Department of Agricultural, Forest and Food Sciences, University of Torino, 10095, Grugliasco, Italy.
| | - Fabiano Sillo
- Department of Agricultural, Forest and Food Sciences, University of Torino, 10095, Grugliasco, Italy.
| | - Elisa Lagostina
- Department of Environmental Sciences, Policy and Management, University of California at Berkeley, CA, 94720, Berkeley, USA. .,Department of Earth and Environmental Sciences, University of Pavia, 27100, Pavia, Italy.
| | - Angela Roccotelli
- Department of Environmental Sciences, Policy and Management, University of California at Berkeley, CA, 94720, Berkeley, USA. .,Department of Agriculture, Mediterranean University of Reggio Calabria, 89122, Reggio Calabria, Italy.
| | - Olga Santa Cacciola
- Department of Agriculture, Food and Environment, University of Catania, 95123, Catania, Italy.
| | - Jan Stenlid
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, 75007, Uppsala, Sweden.
| | - Matteo Garbelotto
- Department of Environmental Sciences, Policy and Management, University of California at Berkeley, CA, 94720, Berkeley, USA.
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32
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Qin Z, Wang Y, Wang Q, Li A, Hou F, Zhang L. Evolution Analysis of Simple Sequence Repeats in Plant Genome. PLoS One 2015; 10:e0144108. [PMID: 26630570 PMCID: PMC4668000 DOI: 10.1371/journal.pone.0144108] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 11/13/2015] [Indexed: 01/30/2023] Open
Abstract
Simple sequence repeats (SSRs) are widespread units on genome sequences, and play many important roles in plants. In order to reveal the evolution of plant genomes, we investigated the evolutionary regularities of SSRs during the evolution of plant species and the plant kingdom by analysis of twelve sequenced plant genome sequences. First, in the twelve studied plant genomes, the main SSRs were those which contain repeats of 1–3 nucleotides combination. Second, in mononucleotide SSRs, the A/T percentage gradually increased along with the evolution of plants (except for P. patens). With the increase of SSRs repeat number the percentage of A/T in C. reinhardtii had no significant change, while the percentage of A/T in terrestrial plants species gradually declined. Third, in dinucleotide SSRs, the percentage of AT/TA increased along with the evolution of plant kingdom and the repeat number increased in terrestrial plants species. This trend was more obvious in dicotyledon than monocotyledon. The percentage of CG/GC showed the opposite pattern to the AT/TA. Forth, in trinucleotide SSRs, the percentages of combinations including two or three A/T were in a rising trend along with the evolution of plant kingdom; meanwhile with the increase of SSRs repeat number in plants species, different species chose different combinations as dominant SSRs. SSRs in C. reinhardtii, P. patens, Z. mays and A. thaliana showed their specific patterns related to evolutionary position or specific changes of genome sequences. The results showed that, SSRs not only had the general pattern in the evolution of plant kingdom, but also were associated with the evolution of the specific genome sequence. The study of the evolutionary regularities of SSRs provided new insights for the analysis of the plant genome evolution.
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Affiliation(s)
- Zhen Qin
- Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Yanping Wang
- Shandong Key Laboratory of Animal Disease Control and Breeding/Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Qingmei Wang
- Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Aixian Li
- Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Fuyun Hou
- Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, China
| | - Liming Zhang
- Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, China
- * E-mail:
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33
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A New Panel of SNP Markers for the Individual Identification of North American Pumas. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2015. [DOI: 10.3996/112014-jfwm-080] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
Pumas Puma concolor are one of the most studied terrestrial carnivores because of their widespread distribution, substantial ecological impacts, and conflicts with humans. Over the past decade, managing pumas has involved extensive efforts including the use of genetic methods. Microsatellites have been the most commonly used genetic markers; however, technical artifacts and little overlap of frequently used loci render large-scale comparison of puma genetic data across studies challenging. Therefore, a panel of genetic markers that can produce consistent genotypes across studies without the need for extensive calibrations is essential for range-wide genetic management of puma populations. Here, we describe the development of PumaPlex, a high-throughput assay to genotype 25 single nucleotide polymorphisms in pumas. We validated PumaPlex in 748 North American pumas Puma concolor couguar, and demonstrated its ability to generate reproducible genotypes and accurately identify individuals. Furthermore, in a test using fecal deoxyribonucleic acid (DNA) samples, we found that PumaPlex produced significantly more genotypes with fewer errors than 12 microsatellite loci, 8 of which are commonly used. Our results demonstrate that PumaPlex is a valuable tool for the genetic monitoring and management of North American puma populations. Given the analytical simplicity, reproducibility, and high-throughput capability of single nucleotide polymorphisms, PumaPlex provides a standard panel of markers that promotes the comparison of genotypes across studies and independent of the genotyping technology used.
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34
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Haasl RJ, Payseur BA. Fifteen years of genomewide scans for selection: trends, lessons and unaddressed genetic sources of complication. Mol Ecol 2015. [PMID: 26224644 DOI: 10.1111/mec.13339] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Genomewide scans for natural selection (GWSS) have become increasingly common over the last 15 years due to increased availability of genome-scale genetic data. Here, we report a representative survey of GWSS from 1999 to present and find that (i) between 1999 and 2009, 35 of 49 (71%) GWSS focused on human, while from 2010 to present, only 38 of 83 (46%) of GWSS focused on human, indicating increased focus on nonmodel organisms; (ii) the large majority of GWSS incorporate interpopulation or interspecific comparisons using, for example F(ST), cross-population extended haplotype homozygosity or the ratio of nonsynonymous to synonymous substitutions; (iii) most GWSS focus on detection of directional selection rather than other modes such as balancing selection; and (iv) in human GWSS, there is a clear shift after 2004 from microsatellite markers to dense SNP data. A survey of GWSS meant to identify loci positively selected in response to severe hypoxic conditions support an approach to GWSS in which a list of a priori candidate genes based on potential selective pressures are used to filter the list of significant hits a posteriori. We also discuss four frequently ignored determinants of genomic heterogeneity that complicate GWSS: mutation, recombination, selection and the genetic architecture of adaptive traits. We recommend that GWSS methodology should better incorporate aspects of genomewide heterogeneity using empirical estimates of relevant parameters and/or realistic, whole-chromosome simulations to improve interpretation of GWSS results. Finally, we argue that knowledge of potential selective agents improves interpretation of GWSS results and that new methods focused on correlations between environmental variables and genetic variation can help automate this approach.
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Affiliation(s)
- Ryan J Haasl
- Department of Biology, University of Wisconsin-Platteville, 1 University Plaza, Platteville, WI, 53818, USA
| | - Bret A Payseur
- Laboratory of Genetics, University of Wisconsin-Madison, 425 Henry Mall, Madison, WI, 53706, USA
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35
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Pramod S, Perkins AD, Welch ME. Patterns of microsatellite evolution inferred from the Helianthus annuus (Asteraceae) transcriptome. J Genet 2015; 93:431-42. [PMID: 25189238 DOI: 10.1007/s12041-014-0402-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The distribution of microsatellites in exons, and their association with gene ontology (GO) terms is explored to elucidate patterns of microsatellite evolution in the common sunflower, Helianthus annuus. The relative position, motif, size and level of impurity were estimated for each microsatellite in the unigene database available from the Compositae Genome Project (CGP), and statistical analyses were performed to determine if differences in microsatellite distributions and enrichment within certain GO terms were significant. There are more translated than untranslated microsatellites, implying that many bring about structural changes in proteins. However, the greatest density is observed within the UTRs, particularly 5'UTRs. Further, UTR microsatellites are purer and longer than coding region microsatellites. This suggests that UTR microsatellites are either younger and under more relaxed constraints, or that purifying selection limits impurities, and directional selection favours their expansion. GOs associated with response to various environmental stimuli including water deprivation and salt stress were significantly enriched with microsatellites. This may suggest that these GOs are more labile in plant genomes, or that selection has favoured the maintenance of microsatellites in these genes over others. This study shows that the distribution of transcribed microsatellites in H. annuus is nonrandom, the coding region microsatellites are under greater constraint compared to the UTR microsatellites, and that these sequences are enriched within genes that regulate plant responses to environmental stress and stimuli.
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Affiliation(s)
- Sreepriya Pramod
- Department of Biological Sciences, Mississippi State University, 219 Harned Hall, 295 Lee Boulevard, MS 39762, USA.
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36
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Haasl RJ, Johnson RC, Payseur BA. The effects of microsatellite selection on linked sequence diversity. Genome Biol Evol 2015; 6:1843-61. [PMID: 25115009 PMCID: PMC4122932 DOI: 10.1093/gbe/evu134] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The genome-wide scan for selection is an important method for identifying loci involved in adaptive evolution. However, theory that underlies standard scans for selection assumes a simple mutation model. In particular, recurrent mutation of the selective target is not considered. Although this assumption is reasonable for single-nucleotide variants (SNVs), a microsatellite targeted by selection will reliably violate this assumption due to high mutation rate. Moreover, the mutation rate of microsatellites is generally high enough to ensure that recurrent mutation is pervasive rather than occasional. It is therefore unclear if positive selection targeting microsatellites can be detected using standard scanning statistics. Examples of functional variation at microsatellites underscore the significance of understanding the genomic effects of microsatellite selection. Here, we investigate the joint effects of selection and complex mutation on linked sequence diversity, comparing simulations of microsatellite selection and SNV-based selective sweeps. We find that selection on microsatellites is generally difficult to detect using popular summaries of the site frequency spectrum, and, under certain conditions, using popular methods such as the integrated haplotype statistic and SweepFinder. However, comparisons of the number of haplotypes (K) and segregating sites (S) often provide considerable power to detect selection on microsatellites. We apply this knowledge to a scan of autosomes in the human CEU population (CEPH population sampled from Utah). In addition to the most commonly reported targets of selection in European populations, we identify numerous novel genomic regions that bear highly anomalous haplotype configurations. Using one of these regions—intron 1 of MAGI2—as an example, we show that the anomalous configuration is coincident with a perfect CA repeat of length 22. We conclude that standard genome-wide scans will commonly fail to detect mutationally complex targets of selection but that comparisons of K and S will, in many cases, facilitate their identification.
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Affiliation(s)
- Ryan J. Haasl
- Laboratory of Genetics, University of Wisconsin – Madison
- Present address: Department of Biology, University of Wisconsin – Platteville, Platteville, WI
- *Corresponding author: E-mail:
| | - Ross C. Johnson
- Department of Biology, University of Wisconsin – Platteville
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37
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Putman AI, Carbone I. Challenges in analysis and interpretation of microsatellite data for population genetic studies. Ecol Evol 2014; 4:4399-428. [PMID: 25540699 PMCID: PMC4267876 DOI: 10.1002/ece3.1305] [Citation(s) in RCA: 237] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 10/02/2014] [Accepted: 10/03/2014] [Indexed: 12/14/2022] Open
Abstract
Advancing technologies have facilitated the ever-widening application of genetic markers such as microsatellites into new systems and research questions in biology. In light of the data and experience accumulated from several years of using microsatellites, we present here a literature review that synthesizes the limitations of microsatellites in population genetic studies. With a focus on population structure, we review the widely used fixation (F ST) statistics and Bayesian clustering algorithms and find that the former can be confusing and problematic for microsatellites and that the latter may be confounded by complex population models and lack power in certain cases. Clustering, multivariate analyses, and diversity-based statistics are increasingly being applied to infer population structure, but in some instances these methods lack formalization with microsatellites. Migration-specific methods perform well only under narrow constraints. We also examine the use of microsatellites for inferring effective population size, changes in population size, and deeper demographic history, and find that these methods are untested and/or highly context-dependent. Overall, each method possesses important weaknesses for use with microsatellites, and there are significant constraints on inferences commonly made using microsatellite markers in the areas of population structure, admixture, and effective population size. To ameliorate and better understand these constraints, researchers are encouraged to analyze simulated datasets both prior to and following data collection and analysis, the latter of which is formalized within the approximate Bayesian computation framework. We also examine trends in the literature and show that microsatellites continue to be widely used, especially in non-human subject areas. This review assists with study design and molecular marker selection, facilitates sound interpretation of microsatellite data while fostering respect for their practical limitations, and identifies lessons that could be applied toward emerging markers and high-throughput technologies in population genetics.
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Affiliation(s)
- Alexander I Putman
- Department of Plant Pathology, North Carolina State University Raleigh, North Carolina, 27695-7616
| | - Ignazio Carbone
- Department of Plant Pathology, North Carolina State University Raleigh, North Carolina, 27695-7616
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Dayan FE, Owens DK, Tranel PJ, Preston C, Duke SO. Evolution of resistance to phytoene desaturase and protoporphyrinogen oxidase inhibitors--state of knowledge. PEST MANAGEMENT SCIENCE 2014; 70:1358-66. [PMID: 24446422 DOI: 10.1002/ps.3728] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 01/06/2014] [Accepted: 01/20/2014] [Indexed: 05/25/2023]
Abstract
Two major classes of herbicides include inhibitors of protoporphyrinogen oxidase (PPO) and phytoene desaturase (PDS). Plants can evolve resistance to PPO and PDS inhibitors via several mechanisms that include physical changes, resulting in reduced uptake, physiological changes, resulting in compartmentalization or altered translocation, and biochemical changes, resulting in enhanced metabolic degradation or alterations of protein structures, leading to loss of sensitivity to the herbicides. This review discusses the involvement of some of these mechanisms in the various cases of resistance to PDS- and PPO-inhibiting herbicides, and highlights unique aspects of target-site resistance to these herbicides.
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Affiliation(s)
- Franck E Dayan
- Natural Products Utilization Research Unit, United States Department of Agriculture - Agricultural Research Service, University, MS, USA
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Abstract
It is widely appreciated that short tandem repeat (STR) variation underlies substantial phenotypic variation in organisms. Some propose that the high mutation rates of STRs in functional genomic regions facilitate evolutionary adaptation. Despite their high mutation rate, some STRs show little to no variation in populations. One such STR occurs in the Arabidopsis thaliana gene PFT1 (MED25), where it encodes an interrupted polyglutamine tract. Although the PFT1 STR is large (∼270 bp), and thus expected to be extremely variable, it shows only minuscule variation across A. thaliana strains. We hypothesized that the PFT1 STR is under selective constraint, due to previously undescribed roles in PFT1 function. We investigated this hypothesis using plants expressing transgenic PFT1 constructs with either an endogenous STR or synthetic STRs of varying length. Transgenic plants carrying the endogenous PFT1 STR generally performed best in complementing a pft1 null mutant across adult PFT1-dependent traits. In stark contrast, transgenic plants carrying a PFT1 transgene lacking the STR phenocopied a pft1 loss-of-function mutant for flowering time phenotypes and were generally hypomorphic for other traits, establishing the functional importance of this domain. Transgenic plants carrying various synthetic constructs occupied the phenotypic space between wild-type and pft1 loss-of-function mutants. By varying PFT1 STR length, we discovered that PFT1 can act as either an activator or repressor of flowering in a photoperiod-dependent manner. We conclude that the PFT1 STR is constrained to its approximate wild-type length by its various functional requirements. Our study implies that there is strong selection on STRs not only to generate allelic diversity, but also to maintain certain lengths pursuant to optimal molecular function.
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40
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Haasl RJ, Payseur BA. Remarkable selective constraints on exonic dinucleotide repeats. Evolution 2014; 68:2737-44. [PMID: 24899386 DOI: 10.1111/evo.12460] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 05/14/2014] [Indexed: 01/07/2023]
Abstract
Long dinucleotide repeats found in exons present a substantial mutational hazard: mutations at these loci occur often and generate frameshifts. Here, we provide clear and compelling evidence that exonic dinucleotides experience strong selective constraint. In humans, only 18 exonic dinucleotides have repeat lengths greater than six, which contrasts sharply with the genome-wide distribution of dinucleotides. We genotyped each of these dinucleotides in 200 humans from eight 1000 Genomes Project populations and found a near-absence of polymorphism. More remarkably, divergence data demonstrate that repeat lengths have been conserved across the primate phylogeny in spite of what is likely considerable mutational pressure. Coalescent simulations show that even a very low mutation rate at these loci fails to explain the anomalous patterns of polymorphism and divergence. Our data support two related selective constraints on the evolution of exonic dinucleotides: a short-term intolerance for any change to repeat length and a long-term prevention of increases to repeat length. In general, our results implicate purifying selection as the force that eliminates new, deleterious mutants at exonic dinucleotides. We briefly discuss the evolution of the longest exonic dinucleotide in the human genome--a 10 x CA repeat in fibroblast growth factor receptor-like 1 (FGFRL1)--that should possess a considerably greater mutation rate than any other exonic dinucleotide and therefore generate a large number of deleterious variants.
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Affiliation(s)
- Ryan J Haasl
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, 53706.
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41
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Abstract
The past fifty years have seen the development and application of numerous statistical methods to identify genomic regions that appear to be shaped by natural selection. These methods have been used to investigate the macro- and microevolution of a broad range of organisms, including humans. Here, we provide a comprehensive outline of these methods, explaining their conceptual motivations and statistical interpretations. We highlight areas of recent and future development in evolutionary genomics methods and discuss ongoing challenges for researchers employing such tests. In particular, we emphasize the importance of functional follow-up studies to characterize putative selected alleles and the use of selection scans as hypothesis-generating tools for investigating evolutionary histories.
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Affiliation(s)
- Joseph J Vitti
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138; ,
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Pascual-Ruiz S, Gómez-Martinez MA, Ansaloni T, Segarra-Moragues JG, Sabater-Muñoz B, Jacas JA, Hurtado-Ruiz MA. Genetic structure of a phytophagous mite species affected by crop practices: the case of Tetranychus urticae in clementine mandarins. EXPERIMENTAL & APPLIED ACAROLOGY 2014; 62:477-498. [PMID: 24233157 DOI: 10.1007/s10493-013-9755-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 11/05/2013] [Indexed: 06/02/2023]
Abstract
Tetranychus urticae Koch is a cosmopolitan mite considered as the most polyphagous species among spider mites. This mite is a key pest of clementine mandarins in Eastern Spain, where Spanish clementine production concentrates. Crop management practices can affect the population dynamics of this mite and, consequently, its impact on the orchard. Microsatellite markers were used to study mite population genetics from two commercial orchards which had been managed differently following Integrated Pest Management (IPM) or Organic Pest Management (OPM) schemes during four consecutive years. A multiplex system including 20 microsatellite loci was designed specifically and allowed an efficient and inexpensive genotyping of individual mites. We found that the IPM population had a stronger fluctuation of population structure and higher genetic diversity compared to OPM population. Thus, our study concludes that crop management has an impact on the population genetics of T. urticae which may be related to the alternation of some acaricides under IPM.
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Doyle JM, Siegmund G, Ruhl JD, Eo SH, Hale MC, Marra NJ, Waser PM, Dewoody JA. Microsatellite analyses across three diverse vertebrate transcriptomes (Acipenser fulvescens, Ambystoma tigrinum, and Dipodomys spectabilis). Genome 2013; 56:407-14. [PMID: 24099393 DOI: 10.1139/gen-2013-0056] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Historically, many population genetics studies have utilized microsatellite markers sampled at random from the genome and presumed to be selectively neutral. Recent studies, however, have shown that microsatellites can occur in transcribed regions, where they are more likely to be under selection. In this study, we mined microsatellites from transcriptomes generated by 454-pyrosequencing for three vertebrate species: lake sturgeon (Acipenser fulvescens), tiger salamander (Ambystoma tigrinum), and kangaroo rat (Dipodomys spectabilis). We evaluated (i) the occurrence of microsatellites across species; (ii) whether particular gene ontology terms were over-represented in genes that contained microsatellites; (iii) whether repeat motifs were located in untranslated regions or coding sequences of genes; and (iv) in silico polymorphism. Microsatellites were less common in tiger salamanders than in either lake sturgeon or kangaroo rats. Across libraries, trinucleotides were found more frequently than any other motif type, presumably because they do not cause frameshift mutations. By evaluating variation across reads assembled to a given contig, we were able to identify repeat motifs likely to be polymorphic. Our study represents one of the first comparative data sets on the distribution of vertebrate microsatellites within expressed genes. Our results reinforce the idea that microsatellites do not always occur in noncoding DNA, but commonly occur in expressed genes.
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Affiliation(s)
- Jacqueline M Doyle
- a Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
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