Protein Phosphatase 2, Methylated (SET) Antibody – Mouse Monoclonal

The protein encoded by this gene inhibits acetylation of nucleosomes, especially histone H4, by histone acetylases (HAT). This inhibition is most likely accomplished by masking histone lysines from being acetylated, and the consequence is to silence HAT-dependent transcription. The encoded protein is part of a complex localized to the endoplasmic reticulum but is found in the nucleus and inhibits apoptosis following attack by cytotoxic T lymphocytes. This protein can also enhance DNA replication of the adenovirus genome. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2011]

SET: a potent inhibitor of protein phosphatase 2A involved in apoptosis, transcription, nucleosome assembly and histone binding. The translocation t(6;9)(q21;q34.1) NUP214/CAN is found in some cases of acute undifferentiated leukemia (AUL). Two alternatively spliced isoforms have been described. Isoform 1 and isoform 2 interact directly with each other and with ANP32A within the tripartite INHAT (inhibitor of acetyltransferases) complex. Both isoforms inhibit the acetylation of histones (HAT) and nucleosomes, most probably by masking the accessibility of lysines of histones to the acetylases. The predominant target for inhibition is histone H4. HAT inhibition leads to silencing of HAT-dependent transcription and prevents active demethylation of DNA. Both isoforms stimulate DNA replication of the adenovirus genome complexed with viral core proteins; however, isoform 2 specific activity is higher. Isoform 2 anti-apoptotic activity is mediated by inhibition of the GZMA-activated DNase, NME1. In the course of cytotoxic T lymphocyte (CTL)-induced apoptosis, GZMA cleaves SET, disrupting its binding to NME1 and releasing NME1 inhibition.

Protein type: Apoptosis; DNA replication; DNA-binding; Inhibitor; Oncoprotein; Nuclear receptor co-regulator

Chromosomal Location of Human Ortholog: 9q34

Cellular Component: nucleoplasm; protein complex; perinuclear region of cytoplasm; endoplasmic reticulum; cytoplasm; cytosol; nucleus

Molecular Function: protein binding; DNA binding; histone binding; protein phosphatase type 2A regulator activity; protein phosphatase inhibitor activity

Biological Process: nucleosome assembly; nucleosome disassembly; regulation of catalytic activity; negative regulation of catalytic activity; nucleocytoplasmic transport; gene expression; negative regulation of neuron apoptosis; mitotic cell cycle; DNA replication; negative regulation of transcription, DNA-dependent; negative regulation of histone acetylation