Cleavage stimulation factor
Cleavage stimulatory factor or cleavage stimulation factor is a heterotrimeric protein, made up of the proteins CSTF1, CSTF2 and CSTF3, totalling about 200 kDa. It is involved in the cleavage of the 3' signaling region from a newly synthesized pre-messenger RNA molecule. CstF is recruited by cleavage and polyadenylation specificity factor and assembles into a protein complex on the 3' end to promote the synthesis of a functional polyadenine tail, which results in a mature mRNA molecule ready to be exported from the cell nucleus to the cytosol for translation.
The amount of CstF in a cell is dependent on the phase of the cell cycle, increasing significantly during the transition from G0 phase to S phase in mouse fibroblast and human splenic B cells.Genes
