Retinoblastoma, Recombinant Fusion Protein, aa701-928, Negative and Positive Control (Rb)

The retinoblastoma tumor suppressor protein Rb regulates cell proliferation by controlling progression through the restriction point within the G1-phase of the cell cycle (1). Rb has three functionally distinct binding domains and interacts with critical regulatory proteins including the E2F family of transcription factors, c-Abl tyrosine kinase and proteins with a conserved LXCXE motif (2-4). Cell cycle-dependent phosphorylation by cdk's inhibits Rb target binding, thus allowing cell cycle progression (5). Rb inactivation and subsequent cell cycle progression likely requires first phosphorylation by cyclin D-cdk4/6 followed by cyclin E-cdk2 phosphorylation (6). Specificity of different cdk/cyclin complexes has been observed in vitro (6-8) and cyclin D1 is required for Ser780 phosphorylation in vivo (9). R1665A Rb-C Fusion Protein Non-Phosphorylated 1x100ul Rb-C is expressed as a recombinant fusion protein of Rb residues 701-928 and maltose binding protein, serves as a negative control. R1665BRb-C Fusion Protein Phosphorylated: 1x100ul Prepared by in vitro kinase reaction with cdc2, serves as a positive control. Application:, Suitable for use as a control in Western Blot. Recommended Dilution: 10ul (50ng), Storage and Stability: May be stored at 4°C for short-term only. For long-term storage, aliquot and store at -20°C. Aliquots are stable for at least 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.