NCBI Summary:
This gene encodes a member of the cyclin family. Cyclins are important regulators of cell cycle transitions through their ability to bind and activate cyclin-dependent protein kinases. This member also belongs to the F-box protein family which is characterized by an approximately 40 amino acid motif, the F-box. The F-box proteins constitute one of the four subunits of the ubiquitin protein ligase complex called SCFs (SKP1-cullin-F-box), which function in phosphorylation-dependent ubiquitination. The F-box proteins are divided into 3 classes: Fbws containing WD-40 domains, Fbls containing leucine-rich repeats, and Fbxs containing either different protein-protein interaction modules or no recognizable motifs. The protein encoded by this gene belongs to the Fbxs class and it was one of the first proteins in which the F-box motif was identified. [provided by RefSeq]
General function
Cell cycle regulation
Comment
Cellular localization
Nuclear
Comment
Ovarian function
Comment
Expression regulated by
Comment
Ovarian localization
Primordial Germ Cell, Oocyte
Comment
Cyclin F regulates the nuclear localization of cyclin B1 through a cyclin-cyclin interaction. Kong M et al. The key regulator of G(2)-M transition of the cell cycle is M-phase promoting factor (MPF), a complex composed of cdc2 and a B-type cyclin. Cyclin B1 nuclear localization involves phosphorylation within a region called the cytoplasmic retention signal, which also contains a nuclear export signal. The mechanism of MPF nuclear localization remains unclear since it contains no functional nuclear localization signal (NLS). We exploited the yeast two-hybrid screen to find protein(s) potentially mediating localization of cyclin B1 and identified a novel interaction between cyclin B1 and cyclin F. We found that cdc2, cyclin B1 and cyclin F form a complex that exhibits histone H1 kinase activity. Cyclin B1 and cyclin F also colocalize through immunofluorescence studies. Additionally, deletion analysis revealed that each putative NLS of cyclin F is functional. Taken together, the data suggest that the NLS regions of cyclin F regulate cyclin B1 localization to the nucleus. The interaction between cyclin B1 and cyclin F represents the first example of direct cyclin-cyclin binding, and elucidates a novel mechanism that regulates MPF localization and function.