Rb Antibody (XZ55): sc-65230

Rb Antibody (XZ55) is a mouse monoclonal IgG1 kappa light chain antibody raised against amino acids 387-982 of human retinoblastoma protein (Rb), a crucial tumor suppressor regulating cell cycle progression. Rb mouse monoclonal antibody (XZ55) recognizes an epitope within the specified immunogen sequence and demonstrates broad species cross-reactivity, detecting Rb in mouse, rat, and human samples through Western blotting (WB), immunoprecipitation (IP), and immunofluorescence (IF) applications. The retinoblastoma protein undergoes precise regulation through phosphorylation during cell cycle progression. During G1 phase, cyclin D (D1, D2, D3)-dependent kinases phosphorylate Rb at Ser795, triggering Rb′s conversion from a transcriptionally repressive, hypophosphorylated state to an inactive, phosphorylated form. This phosphorylation state can persist through mitosis through modifications at up to 16 potential serine or threonine residues, including Ser249/Thr252, Thr373, Thr356, Ser780, Ser807/Ser811, and Thr821/Thr826. In hypophosphorylated form, Rb suppresses cell cycle-related gene transcription through two primary mechanisms: direct protein-protein interactions that inactivate transcription factor promoters, and recruitment of histone deacetylase, which removes acetyl groups from promoter regions to enhance nucleosome formation and mask transcription-enhancing elements. Rb predominantly resides in the nucleus, where Rb maintains genomic stability by controlling genes essential for DNA replication and cell proliferation. This nuclear localization proves critical as Rb directly interacts with E2F transcription factors to inhibit cell cycle progression. Mutations disrupting Rb′s proper localization or function can lead to uncontrolled cell division, contributing to retinoblastoma in pediatric patients and various other human tumors. Anti-Rb monoclonal antibody (XZ55) serves as a valuable tool for investigating these sophisticated regulatory mechanisms and their roles in tumor suppression.

The preferred Rb antibody is Rb Antibody (IF8): sc-102.