Colony-stimulating factor 1 regulates novel cyclins during the G1 phase of the cell cycle.
Three mouse cyclin-like (CYL) genes were isolated, two of which are regulated by colony-stimulating factor 1 (CSF-1) during the G1 phase of the macrophage cell cycle. CSF-1 deprivation during G1 leads to rapid degradation of CYL proteins (p36CYL) and correlates with failure to initiate DNA synthesis. However, after entering S phase, macrophages no longer require CSF-1 and can complete cell division without expressing CYL genes. During G1, p36CYL is phosphorylated and associates with a polypeptide antigenically related to p34cdc2. The timing of p36CYL expression, its rapid turnover in the absence of CSF-1, and its phosphorylation and transient binding to a cdc2-related polypeptide suggest that CYL genes may function during S phase commitment.
Matsushime
H
H
Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
Roussel
M F
MF
Ashmun
R A
RA
Sherr
C J
CJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle; D002460:Cell Line; D003001:Cloning, Molecular; D016213:Cyclins / Q000235:genetics*; D016193:G1 Phase; D005786:Gene Expression Regulation; D015723:Gene Library; D007700:Kinetics; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D012689:Sequence Homology, Nucleic Acid
D016213:Cyclins; D016173:Macrophage Colony-Stimulating Factor