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Title: Supergene potential of a selfish centromere
Selfishly evolving centromeres bias their transmission by exploiting the asymmetry of female meiosis and preferentially segregating to the egg. Such female meiotic drive systems have the potential to be supergenes, with multiple linked loci contributing to drive costs or enhancement. Here, we explore the supergene potential of a selfish centromere ( D ) in Mimulus guttatus , which was discovered in the Iron Mountain (IM) Oregon population. In the nearby Cone Peak population, D is still a large, non-recombining and costly haplotype that recently swept, but shorter haplotypes and mutational variation suggest a distinct population history. We detected D in five additional populations spanning more than 200 km; together, these findings suggest that selfish centromere dynamics are widespread in M. guttatus . Transcriptome comparisons reveal elevated differences in expression between driving and non-driving haplotypes within, but not outside, the drive region, suggesting large-scale cis effects of D 's spread on gene expression. We use the expression data to refine linked candidates that may interact with drive, including Nuclear Autoantigenic Sperm Protein (NASP SIM3 ), which chaperones the centromere-defining histone CenH3 known to modify Mimulus drive. Together, our results show that selfishly evolving centromeres may exhibit supergene behaviour and lay the foundation for future genetic dissection of drive and its costs. This article is part of the theme issue ‘Genomic architecture of supergenes: causes and evolutionary consequences’.  more » « less
Award ID(s):
1736249
PAR ID:
10356581
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Philosophical Transactions of the Royal Society B: Biological Sciences
Volume:
377
Issue:
1856
ISSN:
0962-8436
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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