Cyclin-dependent kinase 4 (EC 2.7.11.22) (Cell division protein kinase 4) (PSK-J3)
1_MATSR 6_ YEPVA 11_ EIGVG 16_ AYGTV 21_ YKARD 26_ PHSGH 31_ FVALK 36_ SVRVP 41_ NGGGG 46_ GGGLP 51_ ISTVR 56_ EVALL 61_ RRLEA 66_ FEHPN 71_ VVRLM 76_ DVCAT 81_ SRTDR 86_ EIKVT 91_ LVFEH 96_ VDQDL 101_ RTYLD 106_ KAPPP 111_ GLPAE 116_ TIKDL 121_ MRQFL 126_ RGLDF 131_ LHANC 136_ IVHRD 141_ LKPEN 146_ ILVTS 151_ GGTVK 156_ LADFG 161_ LARIY 166_ SYQMA 171_ LTPVV 176_ VTLWY 181_ RAPEV 186_ LLQST 191_ YATPV 196_ DMWSV 201_ GCIFA 206_ EMFRR 211_ KPLFC 216_ GNSEA 221_ DQLGK 226_ IFDLI 231_ GLPPE 236_ DDWPR 241_ DVSLP 246_ RGAFP 251_ PRGPR 256_ PVQSV 261_ VPEME 266_ ESGAQ 271_ LLLEM 276_ LTFNP 281_ HKRIS 286_ AFRAL 291_ QHSYL 296_HKDEG
1: Ser/Thr-kinase component of cyclin D-CDK4 (DC) complexes that phosphorylate and inhibit members of the retinoblastoma (RB) protein family including RB1 and regulate the cell-cycle during G(1)/S transition. Phosphorylation of RB1 allows dissociation of the transcription factor E2F from the RB/E2F complexes and the subsequent transcription of E2F target genes which are responsible for the progression through the G(1) phase. Hypophosphorylates RB1 in early G(1) phase. Cyclin D-CDK4 complexes are major integrators of various mitogenenic and antimitogenic signals. Also phosphorylates SMAD3 in a cell-cycle-dependent manner and represses its transcriptional activity. Component of the ternary complex, cyclin D/CDK4/CDKN1B, required for nuclear translocation and activity of the cyclin D-CDK4 complex