DNA-directed RNA polymerase III subunit B (POLR3B)

DNA-directed RNA polymerase III subunit B (POLR3B) is a core component of the multisubunit RNA polymerase III complex, which is conserved in all eukaryotes and is essential for the transcription of short untranslated RNAs, including transfer RNAs (tRNAs), 5S ribosomal RNA, U6 small nuclear RNA, and several other small RNAs critical for basic cellular functions such as protein synthesis and RNA processing[2][4][5][6]. POLR3B serves as a structural and functional counterpart within the polymerase core, contributing to the enzyme's assembly, DNA binding, and catalytic activities. Mutations in POLR3B cause a range of severe, primarily neurological diseases such as hypomyelinating leukodystrophy, highlighting its critical importance for human health[1][2][3][5]. There are currently no selective pharmacological modulators of POLR3B, and its ubiquitous and essential function in housekeeping transcription presents substantial challenges for therapeutic targeting.

Other names

DNA-directed RNA polymerase III subunit RPC2RNA polymerase III subunit C2RPC2FLJ10388C128CMT1IHLD8INMAPinterphase nucleus and mitotic apparatus associated proteinpolymerase (RNA) III (DNA directed) polypeptide Bpolymerase (RNA) III subunit B

Not established for clinically used drugs specifically targeting POLR3B. In experimental settings, polymerase inhibitors act by inhibiting RNA synthesis, leading to cessation of small RNA production and interfering with cellular homeostasis.