Global Analysis of CPEBs Reveals Sequential and Non-Redundant Functions in Mitotic Cell Cycle

PLoS One. 2015 Sep 23;10(9):e0138794. doi: 10.1371/journal.pone.0138794. eCollection 2015.

Abstract

CPEB (Cytoplasmic Polyadenylation Element Binding) proteins are a family of four RNA-binding proteins that regulate the translation of maternal mRNAs controlling meiotic cell cycle progression. But CPEBs are not limited to the transcriptionally silent germline; they are also expressed, in various combinations, in somatic cells, yet their role in regulation of mitosis-related gene expression is largely unknown. Deregulation of CPEB1 and CPEB4 have been linked to tumor development. However, a systematic analysis addressing their requirements for the temporal regulation of mitotic gene expression has yet to be performed. This study addresses the requirements of each of the four CPEBs for mitotic phase transitions, with a particular focus on cytoplasmic polyadenylation and translational regulation. We demonstrate that CPEB3 is the only member dispensable for mitotic cell division, whereas the other three members, CPEB1, 2, and 4, are essential to successful mitotic cell division. Thus, CPEB1 is required for prophase entry, CPEB2 for metaphase and CPEB4 for cytokinesis. These three CPEBs have sequential non-redundant functions that promote the phase-specific polyadenylation and translational activation of CPE-regulated transcripts in the mitotic cell cycle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gene Knockdown Techniques
  • HEK293 Cells
  • Humans
  • Mitosis*
  • Polyadenylation
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / physiology*
  • Transcription Factors / physiology*
  • Transcriptome
  • mRNA Cleavage and Polyadenylation Factors / physiology*

Substances

  • CPEB1 protein, human
  • CPEB2 protein, human
  • CPEB4 protein, human
  • RNA, Messenger
  • RNA-Binding Proteins
  • Transcription Factors
  • mRNA Cleavage and Polyadenylation Factors

Grants and funding

This project was supported by the Fundación Botín and the Banco Santander through its Santander Universities Global Division, and by the Spanish Ministerio de Economia y Competitividad (BFU2011-30121 and Consolider RNAREG CSD2009-00080). VG was the recipient of an FPI fellowship from the Ministerio de Economia y Competitividad. F-AB was the recipient of predoctoral fellowship from “Fundació La Caixa”.