Abstract
Female meiosis provides an opportunity for selfish genetic elements to violate Mendel's law of segregation by increasing the chance of segregating to the egg [1]. Centromeres and other repetitive sequences can drive in meiosis by cheating the segregation process [2], but the underlying mechanisms are unknown. Here, we show that centromeres with more satellite repeats house more nucleosomes that confer centromere identity, containing the histone H3 variant CENP-A, and bias their segregation to the egg relative to centromeres with fewer repeats. CENP-A nucleosomes predominantly occupy a single site within the repeating unit that becomes limiting for centromere assembly on smaller centromeres. We propose that amplified repetitive sequences act as selfish elements by promoting expansion of CENP-A chromatin and increased transmission through the female germline.
Keywords:
CENP-A; centromere; chromosome; epigenetics; histone; meiosis; meiotic drive; nucleosome; oocyte; satellite DNA.