RISC-Loading Complex Subunit TARBP2 (TARBP2) Human Recombinant Protein

HIV-1, the causative agent of acquired immunodeficiency syndrome (AIDS), contains an RNA genome that produces a chromosomally integrated DNA during the replicative cycle. Activation of HIV-1 gene expression by the transactivator Tat is dependent on an RNA regulatory element (TAR) located downstream of the transcription initiation site. The protein encoded by this gene binds between the bulge and the loop of the HIV-1 TAR RNA regulatory element and activates HIV-1 gene expression in synergy with the viral Tat protein. Alternative splicing results in multiple transcript variants encoding different isoforms. This gene also has a pseudogene. [provided by RefSeq, Jul 2008]

TRBP: the HIV-1 TAR RNA binding protein (TRBP) is a double strand RNA binding protein (dsRBP) that is required for the recruitment of Ago2 to the small interfering RNA (siRNA) bound by Dicer. TRBP increases HIV-1 expression and replication by inhibiting the interferon-induced protein kinase PKR and by increasing translation of viral mRNA. Dicer, Ago2, and TRBP are the main components of the RNA-induced silencing complex (RISC).

Protein type: RNA-binding; Motility/polarity/chemotaxis; RNA processing; Translation

Chromosomal Location of Human Ortholog: 12q13.13

Cellular Component: nucleoplasm; perinuclear region of cytoplasm; cytoplasm; cytosol; nucleus

Molecular Function: protein binding; protein homodimerization activity; miRNA binding; siRNA binding; double-stranded RNA binding

Biological Process: regulation of transcription from RNA polymerase II promoter; regulation of translation; positive regulation of viral genome replication; regulation of transcription, DNA-dependent; regulation of viral transcription; pre-microRNA processing; RNA interference, targeting of mRNA for destruction; miRNA-mediated gene silencing, miRNA loading onto RISC; negative regulation of protein kinase activity; gene expression; negative regulation of defense response to virus by host; RNA interference, production of siRNA