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Title: Development of a homeolog-specific gene editing system in an evolutionary model for the study of polyploidy in nature
Polyploidy, or whole-genome duplication (WGD), is a significant evolutionary force. Following allopolyploidy, duplicate gene copies (homeologs) have divergent evolutionary trajectories: some genes are preferentially retained in duplicate, while others tend to revert to single-copy status. Examining the effect of homeolog loss (i.e., changes in gene dosage) on associated phenotypes is essential for unraveling the genetic mechanisms underlying polyploid genome evolution. However, homeolog-specific editing has been demonstrated in only a few crop species and remains unexplored beyond agricultural applications.Tragopogon(Asteraceae) includes an evolutionary model system for studying the immediate consequences of polyploidy in nature. In this study, we developed a CRISPR-mediated homeolog-specific editing platform in allotetraploidT. mirus. Using theMYB10andDFRgenes as examples, we successfully knocked out the targeted homeolog inT. mirus(4x) without editing the other homeolog (i.e., no off-target events). The editing efficiencies, defined as the percentage of plants with at least one allele of the targeted homeolog modified, were 35.7% and 45.5% forMYB10andDFR, respectively. Biallelic modification of the targeted homeolog occurred in the T0generation. These results demonstrate the robustness of homeolog-specific editing in polyploidTragopogon, laying the foundation for future studies of genome evolution following WGD in nature.  more » « less
Award ID(s):
1923234
PAR ID:
10662354
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Frontiers Media, SA
Date Published:
Journal Name:
Frontiers in Genome Editing
Volume:
7
ISSN:
2673-3439
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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