Description_x000D_ General description_x000D_ Cyclin C is a member of the cyclin family of proteins. The gene encoding it is localized on human chromosome 6q16.2._x000D_ Biochem/physiol Actions_x000D_ Cyclin C interacts with the cyclin-dependent kinase 8 (CDK8) and induces the phosphorylation of the carboxy-terminal domain of the large subunit of RNA polymerase II. The mRNA levels of Cyclin C fluctuate during the cell cycle and peak at the G1 phase. Cyclin C acts as a critical regulator of the G0/G1 transition of human hematopoietic stem cells. Cyclin C can also associate with CDK3 to enhance retinoblastoma phosphorylation at S807/811 during the G0/G1 transition, and this phosphorylation is required for cells to exit G0 efficiently._x000D_ Physical form_x000D_ Supplied in 50 mM Tris-HCl, pH 7.5, 150 mM NaCl, 10 mM glutathione, 0.1 mM EDTA, 0.25 mM DTT, 0.1 mM PMSF, 25% glycerol._x000D_ Preparation Note_x000D_ After opening, aliquot into smaller quantities and store at -70 °C. Avoid repeating handling and multiple freeze/thaw cycles.