Phosphoproteomic identification of Mos-MAPK targets in meiotic cell cycle and asymmetric oocyte divisions.

ABSTRACT: The Mos kinase activates the ERK/MAPK pathway during oocyte meiosis, controlling essential meiotic functions in species across metazoa. However, despite its significance, the molecular targets of Mos-MAPK remain largely unidentified. Here, we addressed this question using starfish oocytes ideally suited to combine cellular assays with phosphoproteomics. This revealed CPE-mediated mRNA polyadenylation as a prominent target of Mos-MAPK, and we show that translation is required to drive the second meiotic division. Secondly, we identify a well-defined subset of cytoskeletal regulators as targets of Mos-MAPK. We show that this regulation is critical to ensure the asymmetry of meiotic divisions, primarily by reducing the growth of astral microtubules. This allows positioning of the spindle dire

SUBMITTER: Avilov I 

PROVIDER: S-EPMC12542822 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature