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Title: Genomic diversifications of five Gossypium allopolyploid species and their impact on cotton improvement
Abstract

Polyploidy is an evolutionary innovation for many animals and all flowering plants, but its impact on selection and domestication remains elusive. Here we analyze genome evolution and diversification for all five allopolyploid cotton species, including economically important Upland and Pima cottons. Although these polyploid genomes are conserved in gene content and synteny, they have diversified by subgenomic transposon exchanges that equilibrate genome size, evolutionary rate heterogeneities and positive selection between homoeologs within and among lineages. These differential evolutionary trajectories are accompanied by gene-family diversification and homoeolog expression divergence among polyploid lineages. Selection and domestication drive parallel gene expression similarities in fibers of two cultivated cottons, involving coexpression networks andN6-methyladenosine RNA modifications. Furthermore, polyploidy induces recombination suppression, which correlates with altered epigenetic landscapes and can be overcome by wild introgression. These genomic insights will empower efforts to manipulate genetic recombination and modify epigenetic landscapes and target genes for crop improvement.

 
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Award ID(s):
1739092 1444552
NSF-PAR ID:
10153567
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Nature Genetics
Volume:
52
Issue:
5
ISSN:
1061-4036
Page Range / eLocation ID:
p. 525-533
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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