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Expression of GRCs during male and female meiosis in sea lamprey (Petromyzon marinus)

ABSTRACT: Many vertebrate species undergo programmed elimination of specific chromosomes during embryogenesis, only retaining these chromosomes in their germ cells. These chromosomes are referred to as germline-restricted chromosomes (GRCs), many of which have been found to harbor genes that are only expressed in the germline. In some species elimination of GRCs occurs in a sex specific manner, with GRCs being transmitted or eliminated by only one sex. While GRCs have been extensively characterized in male sea lampreys (Petromyzon marinus), the status of GRCs in females has not yet been resolved, though it has been hypothesized that these chromosomes might provide a solution to resolving the long-standing mystery of lamprey sex determining mechanisms. To gain insight into the roles of GRCs in female lampreys, we performed several karyological, transcriptional and genomic analyses, which demonstrate that GRCs are present in female lamprey germline, transmitted by oocytes and somatically eliminated in both sexes. These analyses also show that GRCs play important roles in the maintenance and development of female germline but provide no evidence for sex-specific variation in the elimination and transmission of lamprey GRCs. These findings underscore the fact that programmed DNA loss has evolved in parallel several times over the course of eukaryotic evolution, and that sex-specific transmission/retention of GRCs likely follows no universal rules.

ORGANISM(S): Petromyzon marinus

PROVIDER: GSE280458 | GEO | 2025/05/26

REPOSITORIES: GEO

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CENP-A Deposition Defines Sequences for Retention and Elimination during Programmed DNA Elimination in Nematode

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