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Title: Evolutionary trajectories of duplicated FT homologues and their roles in soybean domestication
Summary

To clarify the molecular bases of flowering time evolution in crop domestication, here we investigate the evolutionary fates of a set of four recently duplicated genes in soybean:FT2a,FT2b,FT2candFT2dthat are homologues of the floral inducerFLOWERING LOCUST(FT). WhileFT2amaintained the flowering inducer function, other genes went through contrasting evolutionary paths.FT2bevolved attenuated expression potentially associated with a transposon insertion in the upstream intergenic region, whileFT2candFT2dobtained a transposon insertion and structural rearrangement, respectively. In contrast toFT2bandFT2dwhose mutational events occurred before the separation ofG. maxandG. soja, the evolution ofFT2cis aG. maxlineage specific event. TheFT2callele carrying a transposon insertion is nearly fixed in soybean landraces and differentiates domesticated soybean from wild soybean, indicating that this allele spread at the early stage of soybean domestication. The domesticated allele causes later flowering than the wild allele under short day and exhibits a signature of selection. These findings suggest thatFT2cmay have underpinned the evolution of photoperiodic flowering regulation in soybean domestication and highlight the evolutionary dynamics of this agronomically important gene family.

 
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NSF-PAR ID:
10034341
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
90
Issue:
5
ISSN:
0960-7412
Page Range / eLocation ID:
p. 941-953
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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