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  • Caught in the Act: Variation in plastid genome inverted repeat expansion within and between populations of Medicago minima
Title: Caught in the Act: Variation in plastid genome inverted repeat expansion within and between populations of Medicago minima
Abstract The inverted repeat (IR) lacking clade (IRLC) is a monophyletic group within the Papilionoideae subfamily of Fabaceae where plastid genomes (plastomes) do not contain the large IR typical of land plants. Recently, an IRLC legume,Medicago minima, was found to have regrown a ~9 kb IR that contained a number of canonical IR genes, and closely relatedM. lupulinacontained an incomplete IR of ~425 bp. Complete plastomes were generated for seven additional species, putative members of theM. minimaclade. Polymerase chain reaction was employed to investigate the presence of the IR acrossM. minimaandM. lupulinaincluding individuals of nine and eight Eurasian and North African accessions and 15 and 14 Texas populations, respectively. While no sequence similar to the ~9 kb IR was detected among the seven newly sequenced plastomes, all Eurasian and North African accessions ofM. minimacontained the IR. Variation in IR extent was detected within and between the Texas populations. Expansions of 13 bp and 11 bp occurred at the boundaries of both IR/small single‐copy regions, and populations had one or the other expansion, but not both. Expansion of the IR was not detected in the accessions from Eurasia and North Africa suggesting recent mutations yielded at least two additional plastid haplotypes inM. minima.  more » « less
Award ID(s):
1853024
PAR ID:
10361015
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Ecology and Evolution
Volume:
10
Issue:
21
ISSN:
2045-7758
Page Range / eLocation ID:
p. 12129-12137
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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