Named for the periodic variation in their concentration, for 10 points, name this family of proteins that control cell cycle progression and which activate a family of kinases abbreviated cdk.
One protein of this family, when complexed with a kinase and contained in the p-TEFb [pee tehf bee] elongation factor, is a cofactor for the HIV-1 protein Tat. One of the "orphan" members of this family is characterized by a forty-residue F-box domain, and the D type is upregulated in the Ras-GTPase pathway and hypophosphorylates retinoblastoma protein. One protein activated by this group of compounds is the serine/threonine kinase p34; that compound binds to the B member of this family of proteins and forms a maturation promoting factor, which controls G2 to M transitions. Named for the periodic variation in their concentration, for 10 points, name this family of proteins that control cell cycle progression and which activate a family of kinases abbreviated cdk.
One protein of this family, when complexed with a kinase and contained in the p-TEFb [pee tehf bee] elongation factor, is a cofactor for the HIV-1 protein Tat.
{cyclins}