Retinoblastoma-like protein 1

Retinoblastoma-like 1 (p107), also known as RBL1, is a is_associated_with::protein that in humans is encoded by the RBL1 is_associated_with::gene.

Function
The protein encoded by this gene is similar in sequence and possibly function to the product of the is_associated_with::retinoblastoma 1 (is_associated_with::RB1) gene. The RB1 gene product is a tumor suppressor protein that appears to be involved in is_associated_with::cell cycle regulation, as it is phosphorylated in the S to M phase transition and is dephosphorylated in the G1 phase of the cell cycle. Both the RB1 protein and the product of this gene can form a complex with is_associated_with::adenovirus E1A protein and is_associated_with::SV40 Large T-antigen, with the is_associated_with::SV40 large T-antigen binding only to the unphosphorylated form of each protein. In addition, both proteins can inhibit the transcription of cell cycle genes containing is_associated_with::E2F binding sites in their promoters. Due to the sequence and biochemical similarities with the RB1 protein, it is thought that the protein encoded by this gene may also be a tumor suppressor. Two transcript variants encoding different is_associated_with::isoforms have been found for this gene.

Interactions
Retinoblastoma-like protein 1 has been shown to interact with is_associated_with::HDAC1, is_associated_with::RBBP8,  is_associated_with::E2F1, is_associated_with::Cyclin-dependent kinase 2,  is_associated_with::BEGAIN, BRF1, is_associated_with::BRCA1, is_associated_with::Cyclin A2, is_associated_with::Prohibitin, is_associated_with::MYBL2 and is_associated_with::Mothers against decapentaplegic homolog 3.