{"symbol":"POLR1B","synonyms":["RPA135","RPO1-2","RPA2"],"name":"polymerase (RNA) I polypeptide B, 128kDa","description":"Eukaryotic RNA polymerase I (pol I) is responsible for the transcription of ribosomal RNA (rRNA) genes and production of rRNA, the primary component of ribosomes. Pol I is a multisubunit enzyme composed of 6 to 14 polypeptides, depending on the species. Most of the mass of the pol I complex derives from the 2 largest subunits, Rpa1 and Rpa2 in yeast. POLR1B is homologous to Rpa2 (Seither and Grummt, 1996 [PubMed 8921381]).[supplied by OMIM, Mar 2008]","ncbiEntrezGeneId":84172,"ncbiEntrezGeneUrl":"http://www.ncbi.nlm.nih.gov/gene/84172","proteins":[{"symbol":"RPA2_HUMAN","href":"/api/1.0/protein/RPA2_HUMAN"}],"hgncRootFamilies":[{"name":"RNA polymerase subunits (POLR)","href":"/api/1.0/gene_family/RNA+polymerase+subunits+%28POLR%29"}]}