High impact information on cig2

• This, and analysis of the temperature sensitive cdc13-117 mutant, suggests that cdc13 can effectively substitute for the G1 cyclin activity of cig2/cyc17 [1].
• Further deletion of cig1 and puc1 had no effect, but deletion of cig2/cyc17 caused a severe delay in re-replication [1].
• Cells lacking cig2 are defective in G1 progression, and this is particularly clear in small cells that must regulate Start with respect to cell size [2].
• The cig2 transcript was found to undergo periodic oscillation during the cell cycle, peaking at the G1/S-phase boundary [3].
• Deletion of cig2 had no observable effect on cell viability or progression through the cell cycle [3].

Biological context of cig2

• Two fission yeast B-type cyclins, cig2 and Cdc13, have different functions in mitosis [4].
• Likewise, a cdc13ts mutation is not rescued by increased gene dosage of cig2+ [4].
• Mitotic phenotypes caused by disruption of cig2 are not reversed by increased production of Cdc13, the other fission yeast B-type cyclin that functions in mitosis [4].
• We found that cells carrying disruptions of both the cig1 and cig2 genes contain multiple nuclei with a 1C DNA content, suggesting that they are delayed in progression through the G1 phase of the cell cycle [3].
• The role of Cig2p during meiosis was investigated using cig2-deleted strains that exhibit delays in onset of both S phase and meiotic divisions as well as an inefficient completion of MII [5].

Other interactions of cig2

• We report the discovery of cig2, a third B-type cyclin gene in Schizosaccharomyces pombe [4].
• We suggest that pheromone signaling inhibits the cig2p-cdc2p kinase, bringing about a transient G1 arrest [6].

References