What does p130 do?

While p130 may serve as a global E2F-dependent repressor during the G0/early G1 phase of the cell cycle, it may also regulate a separate subset of E2F dependent gene expression. There is evidence that pRB and p130 may regulate a subset of E2F dependent genes.

What is p107 protein?

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

What is E2F in cell cycle?

Introduction. The E2 factor (E2F) family of transcription factors are downstream effectors of the retinoblastoma (RB) protein pathway and are believed to play a pivotal role in cell division control. Since its discovery, E2F has been viewed as a positive regulator of genes required for DNA synthesis.

What is p107 biology?

Pocket protein p107 binds and sequesters cyclin E (cycE)/cyclin-dependent kinase 2 (cdk2) complexes. From: Microbes and Infection, 2004.

Is E2F an activator?

E2F is a group of genes that encodes a family of transcription factors (TF) in higher eukaryotes. Three of them are activators: E2F1, 2 and E2F3a. Six others act as suppressors: E2F3b, E2F4-8. All of them are involved in the cell cycle regulation and synthesis of DNA in mammalian cells.

Is E2F a tumor suppressor?

This has highlighted E2F1 as both a tumor-suppressor gene and an oncogene, depending on the context. As E2F-RB1 complexes are repressive, loss of E2Fs could also lead to de-repression of genes involved in cell cycle progression, potentially explaining why loss of E2F can contribute to oncogenesis.

Is E2F a tumor suppressor gene?

E2F is the principal target of the tumor suppressor pRB and defects in the RB pathway are observed in almost all cancers. Upon oncogenic changes, E2F activates ARF , an upstream activator of p53 and TAp73 , resulting in the induction of apoptosis.

How is E2F altered in cancerous cells?

E2Fs linked to human cancer As a whole, E2F repressors may be expected to behave as tumour suppressors, and activators as oncogenes. Therefore, oncogenic alterations of repressor E2F genes would include loss-of-function mutations, chromosomal deletions and/or epigenetic silencing.

Does p53 inhibit E2F?

It was found that p53 specifically inhibited activated transcription by E2F-5 but not by E2F-1. Investigation into the mechanism of action established that heterodimer formation and the DNA-binding steps were not significantly inhibited by p53.

How is Rb phosphorylated?

Rb proteins can be phosphorylated both on A/B domains of the pocket region and on the C-terminal domain. The main hypothesis is that the phosphorylation at the carboxy terminus of pRb by cyclin D/cdk4 (or ckd6) causes a conformational modification, which displaces the HDAC bound to pRb through its LXCXE motif.