Equalizing epigenetically imprinted centromeres in early mammalian embryos

Autor: Gabriel Manske, Kelsey Jorgensen, Binbin Ma, Mansour Aboelenain, Catherine Tower, Saikat Chakraborty, Rajesh Ranjan, Arunika Das, Michael A. Lampson, Ben E. Black, Karen Schindler, Xin Chen, Saher Sue Hammoud
Rok vydání: 2022
DOI: 10.1101/2022.10.27.514094
Popis: SummaryThe CENP-A histone variant epigenetically defines centromeres, where its levels and locations are precisely maintained through mitotic cell divisions. However, differences in centromere CENP-A propagation in soma versus female/male germline remains poorly understood. Here, we generated CenpamScarletmice and followed CENP-A dynamics in gametes, zygotes, and embryos. We found that, unlike somatic cells, progenitor female and male germ cells carry high centromeric CENP-A levels that decrease upon terminal differentiation. The reduction in CENP-A is differentially regulated between sexes, resulting in a ten-fold higher level in oocytes compared to sperm. In the zygote, the parent-of-origin CENP-A asymmetry is equalized prior to initial S-phase by redistribution of nuclear CENP-A from maternal to paternal chromosomes. Redistribution of CENP-A requires both CDK1/2 and PLK1 centromeric machinery. These experiments provide direct evidence for resetting of epigenetically imprinted centromeres in early pronuclear stage embryos and imply a mechanism to sense the non-equivalency of parental chromosomes.HighlightsIncreased CENP-A density at centromeres is a conserved property of germline stem cells while CENP-A reduction is coincident with germ cell differentiationPaternal and maternal CENP-A containing nucleosomes are intergenerationally inheritedCENP-A density at centromeres differs between male and female mature gametesUpon fertilization, maternal nuclear CENP-A is redistributed to equalize with parental CENP-ACENP-C and MIS18BP1 are asymmetrically enriched in the parental pronuclei in accordance with CENP-A asymmetry.Licensing for centromere equalization begins before zygotic DNA replication
Databáze: OpenAIRE