Anti-Cyclin-dependent kinase 4 Cdk4 Antibody Picoband®

Cyclin-dependent kinase-4 (CDK4) is a protein-serine kinase involved in the cell cycle. Human cell division is regulated primarily at the G1-to-S or the G2-to-M boundaries within the cell cycle. The complexes formed by CDK4 and the D-type cyclins are involved in the control of cell proliferation during the G1 phase. CDK4 is inhibited by p16, also known as cyclin-dependent kinase inhibitor-2. CDK4 is mapped to 12q14. CDK4 expression and activity are required for cytokine responsiveness in T cells.

A synthetic peptide corresponding to a sequence at the C-terminus of mouse Cdk4, different from the related rat sequence by one amino acid, and from the related human sequence by four amino acids.

Expressed (at protein level) in a wide range of tissues with highest levels in brain, spinal cord, testis, pancreas, heart, spleen and mammary glands. Moderate levels found in thymus, ovary and small intestine. Not detected in salivary gland, muscle or liver. Also expressed in cell lines of myeloid, fibroblast and epithelial origin. Not detected in most lymphoid cell lines. .

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 (By similarity) . .

1. Demetrick, D. J.; Zhang, H.; Beach, D. H. : Chromosomal mapping of human CDK2, CDK4, and CDK5 cell cycle kinase genes. Cytogenet. Cell Genet. 66: 72-74, 1994. 2. Modiano, J. F.; Mayor, J.; Ball, C.; Fuentes, M. K.; Linthicum, D. S. : CDK4 expression and activity are required for cytokine responsiveness in T cells. J. Immun. 165: 6693-6702, 2000.e for human proliferating nuclear antigen/cyclin by in situ hybridization. Hum. Genet. 86: 84-86, 1990.

Store at -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freeze-thaw cycles.

Cytoplasm . Nucleus . Membrane . Cytoplasmic when non- complexed. Forms a cyclin D-CDK4 complex in the cytoplasm as cells progress through G (1) phase. The complex accumulates on the nuclear membrane and enters the nucleus on transition from G (1) to S phase. Also present in nucleoli and heterochromatin lumps. Colocalizes with RB1 after release into the nucleus (By similarity) . .