1
|
Liu Q, Ye L, Li M, Wang Z, Xiong G, Ye Y, Tu T, Schwarzacher T, Heslop-Harrison JSP. Genome-wide expansion and reorganization during grass evolution: from 30 Mb chromosomes in rice and Brachypodium to 550 Mb in Avena. BMC PLANT BIOLOGY 2023; 23:627. [PMID: 38062402 PMCID: PMC10704644 DOI: 10.1186/s12870-023-04644-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023]
Abstract
BACKGROUND The BOP (Bambusoideae, Oryzoideae, and Pooideae) clade of the Poaceae has a common ancestor, with similarities to the genomes of rice, Oryza sativa (2n = 24; genome size 389 Mb) and Brachypodium, Brachypodium distachyon (2n = 10; 271 Mb). We exploit chromosome-scale genome assemblies to show the nature of genomic expansion, structural variation, and chromosomal rearrangements from rice and Brachypodium, to diploids in the tribe Aveneae (e.g., Avena longiglumis, 2n = 2x = 14; 3,961 Mb assembled to 3,850 Mb in chromosomes). RESULTS Most of the Avena chromosome arms show relatively uniform expansion over the 10-fold to 15-fold genome-size increase. Apart from non-coding sequence diversification and accumulation around the centromeres, blocks of genes are not interspersed with blocks of repeats, even in subterminal regions. As in the tribe Triticeae, blocks of conserved synteny are seen between the analyzed species with chromosome fusion, fission, and nesting (insertion) events showing deep evolutionary conservation of chromosome structure during genomic expansion. Unexpectedly, the terminal gene-rich chromosomal segments (representing about 50 Mb) show translocations between chromosomes during speciation, with homogenization of genome-specific repetitive elements within the tribe Aveneae. Newly-formed intergenomic translocations of similar extent are found in the hexaploid A. sativa. CONCLUSIONS The study provides insight into evolutionary mechanisms and speciation in the BOP clade, which is valuable for measurement of biodiversity, development of a clade-wide pangenome, and exploitation of genomic diversity through breeding programs in Poaceae.
Collapse
Affiliation(s)
- Qing Liu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.
- South China National Botanical Garden, Guangzhou, 510650, China.
- Center for Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou, 510650, China.
| | - Lyuhan Ye
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mingzhi Li
- Bio&Data Biotechnologies Co. Ltd, Guangzhou, 510663, China
| | - Ziwei Wang
- Henry Fok School of Biology and Agriculture, Shaoguan University, Shaoguan, 512005, China
| | - Gui Xiong
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yushi Ye
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
- South China National Botanical Garden, Guangzhou, 510650, China
| | - Tieyao Tu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
- South China National Botanical Garden, Guangzhou, 510650, China
- Center for Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou, 510650, China
| | - Trude Schwarzacher
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China
- Department of Genetics and Genome Biology, Institute for Environmental Futures, University of Leicester, Leicester, LE1 7RH, UK
| | - John Seymour Pat Heslop-Harrison
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, China.
- Department of Genetics and Genome Biology, Institute for Environmental Futures, University of Leicester, Leicester, LE1 7RH, UK.
| |
Collapse
|