Four Subunits That Are Shared by the Three Classes of RNA Polymerase Are Functionally Interchangeable between Homo sapiens and Saccharomyces cerevisiae

• DOI: 10.1128/mcb.15.9.4702
• Publication Date: 2015-10-09T00:17:22Z
• Authors: George V. Shpakovski; Joël Acker; Marguerite Wintze...; Jean-François Lac...; Pierre Thuriaux; Marc Vigneron
• Keywords: RNA polymerase I

Four cDNAs encoding human polypeptides hRPB7.0, hRPB7.6, hRPB17, and hRPB14.4 (referred to as Hs10 alpha, beta, Hs8, Hs6, respectively), homologous the ABC10 ABC14.5, ABC23 RNA polymerase subunits Sc10 Sc8, Sc6, respectively) of Saccharomyces cerevisiae, were cloned characterized for their ability complement defective yeast mutants. alpha corresponding Sp10 Schizosaccharomyces pombe can an S. cerevisiae mutant (rpc10-delta::HIS3) in alpha. The peptide sequences are highly conserved carboxy-terminal halves, with invariant motif CX2CX12RCX2CGXR a canonical zinc-binding domain. N subunit archaeal homologous. An CX2CGXnCCR presumably forms atypical but not subunit, complemented (rpb10-delta 1::HIS3) lacking beta. Hs8 (rpb8-delta 1::LYS2) Sc8 although strong thermosensitive phenotype. Interspecific complementation also occurred Hs6 Dm6 cDNA Drosophila melanogaster. Sp6 dosage-dependent suppressors rpo21-4, mutation generating slowly growing largest II. Finally, doubly chimeric strain bearing beta was viable. No interspecific observed hRPB25 (Hs5) homolog ABC27 (Sc5) subunit.