Distinct regions of RPB11 are required for heterodimerization with RPB3 in human and yeast RNA polymerase II.
In Saccharomyces cerevisiae, RNA polymerase II assembly is probably initiated by the formation of the RPB3-RPB11 heterodimer. RPB3 is encoded by a single copy gene in the yeast, mouse and human genomes. The RPB11 gene is also unique in yeast and mouse, but in humans a gene family has been identified that potentially encodes several RPB11 proteins differing mainly in their C-terminal regions. We compared the abilities of both yeast and human proteins to heterodimerize. We show that the yeast RPB3/RPB11 heterodimer critically depends on the presence of the C-terminal region of RPB11. In contrast, the human heterodimer tolerates significant changes in RPB11 C-terminus, allowing two human RPB11 variants to heterodimerize with the same efficiency with RPB3. In keeping with this observation, the interactions between the conserved N-terminal 'alpha-motifs' is much more important for heterodimerization of the human subunits than for those in yeast. These data indicate that the heterodimerization interfaces have been modified during the course of evolution to allow a recent diversification of the human RPB11 subunits that remains compatible with heterodimerization with RPB3.
Unité Mixte de Recherche 7100 CNRS-Université Louis Pasteur, Ecole Supérieure de Biotechnologie de Strasbourg Boulevard Sébastien Brandt, BP 10413, 67412 Illkirch Cedex, France.
Wagane J
WJ
Benga
Sylvie
S
Grandemange
George V
GV
Shpakovski
Elena K
EK
Shematorova
Claude
C
Kedinger
Marc
M
Vigneron
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D049109:Cell Proliferation; D017124:Conserved Sequence; D019281:Dimerization; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D012319:RNA Polymerase II / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D020798:Two-Hybrid System Techniques
D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; C491783:POLR2C protein, human; C502087:POLR2J protein, human; D012319:RNA Polymerase II; C502086:RPB11 protein, S cerevisiae; C112110:RPB3 protein, S cerevisiae