Component of the BHC complex, a corepressor complex that represses transcription of neuron-specific genes in non-neuronal cells. The BHC complex is recruited at RE1/NRSE sites by REST and acts by deacetylating and demethylating specific sites on histones, thereby acting as a chromatin modifier. In the BHC complex, it may act as a scaffold. Inhibits KDM1A-mediated demethylation of 'Lys-4' of histone H3 in vitro, suggesting a role in demethylation regulation.
LSD1 is a recently identified human lysine (K)-specific histone demethylase. LSD1 is associated with HDAC1/2; CoREST, a SANT domain-containing corepressor; and BHC80, a PHD domain-containing protein, among others. We show that CoREST endows LSD1 with the ability to demethylate nucleosomal substrates and that it protects LSD1 from proteasomal degradation in vivo. We find hyperacetylated nucleosomes less susceptible to CoREST/LSD1-mediated demethylation, suggesting that hypoacetylated nucleosomes may be the preferred physiological substrates. This raises the possibility that histone deacetylases and LSD1 may collaborate to generate a repressive chromatin environment. Consistent with this model, TSA treatment results in derepression of LSD1 target genes. While CoREST positively regulates LSD1 function, BHC80 inhibits CoREST/LSD1-mediated demethylation in vitro and may therefore confer negative regulation. Taken together, these findings suggest that LSD1-mediated histone demethylation is regulated dynamically in vivo. This is expected to have profound effects on gene expression under both physiological and pathological conditions.
Interacting selectively and non-covalently with chromatin, the network of fibers of DNA, protein, and sometimes RNA, that make up the chromosomes of the eukaryotic nucleus during interphase.
BRAF-HDAC complex (BHC) has been shown to contain six components, including BHC80, and to mediate REST-dependent transcriptional repression of neuron-specific genes in non-neuronal cells. In this study, we have examined the functional role(s) of BHC80 in mouse tissues and human cultured cells. Two isoforms of mouse BHC80 were predominantly present in the central nervous system and spermatogenic cells. Human cultured cells also contained two isoforms of BHC80. Immunohistochemical analysis showed the presence of mouse BHC80 in the nucleus of neuronal cells in the hippocampus and cerebellum. The C-terminal region of human BHC80 containing PHD zinc-finger domain was capable of binding directly to each of five other components of BHC, and of organizing BHC mediating transcriptional repression. Moreover, two isoforms of human BHC80 were distinguished from each other by reduced binding to HDAC1 and HDAC2, despite the presence of the PHD finger domain. These results suggest that BHC80 presumably serves as a scaffold protein in BHC in neuronal as well as non-neuronal cells. A possible role of BHC80 in spermatogenesis is also suggested.
Protein involved in the transfer of genetic information from DNA to messenger RNA (mRNA) by DNA-directed RNA polymerase. In the case of some RNA viruses, protein involved in the transfer of genetic information from RNA to messenger RNA (mRNA) by RNA-directed RNA polymerase.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.