Conserved C-terminal domains of mCenp-F (LEK1) regulate subcellular localization and mitotic checkpoint delay.
Centromeric Protein-F (Cenp-F) family members have been identified in organisms from yeast to human. Cenp-F proteins are a component of kinetochores during mitosis, bind to the Rb family of tumor suppressors, and have regulatory effects on the cell cycle and differentiation; however, their role in these processes has not been resolved. Here, we provide evidence that the role of murine Cenp-F (mCenp-F, also known as LEK1) remains largely conserved and that the domains within the C-terminus collectively function to regulate the G2/M cell cycle checkpoint. Overexpression of the C-terminal domain of mCenp-F decreases DNA synthesis. Analyses of deletion mutants of mCenp-F reveal that the complete C-terminal domain is required to delay cell cycle progression at G2/M. Signal transduction pathway profiling experiments indicate that the mCenp-F-mediated cell cycle delay does not involve transcriptional activity of key cell cycle regulators such as Rb, E2F, p53, or Myc. However, endogenous mCenp-F colocalizes with pRb and p107, which demonstrates in vivo protein-protein interaction during cell division. These observations suggest that the domains of the C-terminus of mCenp-F have a conserved function in control of mitotic progression through protein-protein interaction with pocket proteins, thus providing a direct connection between cell cycle regulation and mitotic progression.
Evans
Heather J
HJ
Department of Cell and Developmental Biology and Anatomy, University of South Carolina School of Medicine, SC, USA.
Edwards
Laura
L
Goodwin
Richard L
RL
D000818:Animals; D018797:Cell Cycle Proteins / Q000032:analysis / Q000378:metabolism; D002455:Cell Division / Q000235:genetics; D002868:Chromosomal Proteins, Non-Histone / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D004252:DNA Mutational Analysis; D004261:DNA Replication; D016195:G2 Phase / Q000235:genetics; D006801:Humans; D042541:Intracellular Space / Q000737:chemistry; D051379:Mice; D008840:Microfilament Proteins; D008938:Mitosis / Q000235:genetics; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D050720:Retinoblastoma-Like Protein p107 / Q000032:analysis / Q000378:metabolism; D017384:Sequence Deletion; D015398:Signal Transduction
D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D008840:Microfilament Proteins; D050720:Retinoblastoma-Like Protein p107; C094772:centromere protein F