Anti-RNA polymerase II/POLR2A Antibody Picoband® Fluoro550 Conjugated

DNA-ed RNA polymerase II subunit RPB1, also known as RPB1, is an enzyme that in humans is encoded by the POLR2A gene. It is mapped to 17p13.1. This gene encodes the largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. The product of this gene contains a carboxy terminal domain composed of heptapeptide repeats that are essential for polymerase activity. These repeats contain serine and threonine residues that are phosphorylated in actively transcribing RNA polymerase. In addition, this subunit, in combination with several other polymerase subunits, forms the DNA binding domain of the polymerase, a groove in which the DNA template is transcribed into RNA.

DNA-ed RNA polymerase II subunit RPB1; RNA polymerase II subunit B1; DNA-ed RNA polymerase II subunit A; DNA-ed RNA polymerase III largest subunit; RNA-ed RNA polymerase II subunit RPB1; POLR2A; POLR2

DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Forms the polymerase active center together with the second largest subunit. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB1 is part of the core element with the central large cleft, the clamp element that moves to open and close the cleft and the jaws that are thought to grab the incoming DNA template. At the start of transcription, a single-stranded DNA template strand of the promoter is positioned within the central active site cleft of Pol II. A bridging helix emanates from RPB1 and crosses the cleft near the catalytic site and is thought to promote translocation of Pol II by acting as a ratchet that moves the RNA-DNA hybrid through the active site by switching from straight to bent conformations at each step of nucleotide addition. During transcription elongation, Pol II moves on the template as the transcript elongates. Elongation is influenced by the phosphorylation status of the C-terminal domain (CTD) of Pol II largest subunit (RPB1), which serves as a platform for assembly of factors that regulate transcription initiation, elongation, termination and mRNA processing. Regulation of gene expression levels depends on the balance between methylation and acetylation levels of tha CTD-lysines. Initiation or early elongation steps of transcription of growth-factors-induced immediate early genes are regulated by the acetylation status of the CTD. Methylation and dimethylation have a repressive effect on target genes expression. (Microbial infection) Acts as an RNA-dependent RNA polymerase when associated with small delta antigen of Hepatitis delta virus, acting both as a replicate and transcriptase for the viral RNA circular genome.

1. Egloff, S., O'Reilly, D., Chapman, R. D., Taylor, A., Tanzhaus, K., Pitts, L., Eick, D., Murphy, S. Serine-7 of the RNA polymerase II CTD is specifically required for snRNA gene expression. Science 318: 1777-1779, 2007. 2. Gnatt, A. L., Cramer, P., Fu, J., Bushnell, D. A., Kornberg, R. D. Structural basis of transcription: an RNA polymerase II elongation complex at 3.3 angstrom resolution. Science 292: 1876-1882, 2001. 3. Haijes, H. A., Koster, M. J. E., Rehmann, H., Li, D., Hakonarson, H., Cappuccio, G., Hancarova, M., Lehalle, D., Reardon, W., Schaefer, G. B., Lehman, A., van de Laar, I. M. B. H., and 32 others. De novo heterozygous POLR2A variants cause a neurodevelopmental syndrome with profound infantile-onset hypotonia. Am. J. Hum. Genet. 105: 283-301, 2019.