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Title: DNA cytosine methylation suppresses meiotic recombination at the sex-determining region
Meiotic recombination between homologous chromosomes is vital for maximizing genetic variation among offspring. However, sex-determining regions are often rearranged and blocked from recombination. It remains unclear whether rearrangements or other mechanisms might be responsible for recombination suppression. Here, we uncover that the deficiency of the DNA cytosine methyltransferase DNMT1 in the green algaChlamydomonas reinhardtiicauses anomalous meiotic recombination at the mating-type locus (MT), generating haploid progeny containing bothplusandminusmating-type markers due to crossovers withinMT. The deficiency of a histone methyltransferase for H3K9 methylation does not lead to anomalous recombination. These findings suggest that DNA methylation, rather than rearrangements or histone methylation, suppresses meiotic recombination, revealing an unappreciated biological function for DNA methylation in eukaryotes.  more » « less
Award ID(s):
2312043
PAR ID:
10634232
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Science Advances
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
41
ISSN:
2375-2548
Subject(s) / Keyword(s):
Chlamydomonas mating-type recombination
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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