Interaction of poly(A) polymerase with the 25-kDa subunit of cleavage factor I.
Mammalian poly(A) polymerase (PAP), a key enzyme in the pre-mRNA 3'-end processing reaction, carries the catalytic domain in the N-terminal region, an RNA binding domain, two nuclear localization signals, and a serine/threonine-rich regulatory domain in the C-terminal region. Using LexA-based yeast two-hybrid screening, we identified a cDNA encoding the 25-kDa subunit of cleavage factor I (CFI-25) as a protein that interacts with the C-terminal region of mouse PAP. The glutathione S-transferase pull-down assay and the immunoprecipitation experiment revealed that PAP directly interacts with CFI-25 and that the C-terminal 69 residues of PAP and the N-terminal 60 residues of CFI-25 are sufficient for the interaction between CFI-25 and PAP. Since CFI is known to function in the assembly of the pre-mRNA 3'-processing complex, this interaction may play an important role in the assembly of the processing complex and/or in the regulation of PAP activity within the complex.
Kim
H
H
Department of Chemistry, Korea Advanced Institute of Science and Technology, Taejon 305-701, Korea.
Lee
Y
Y
D000818:Animals; D020134:Catalytic Domain; D018076:DNA, Complementary / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D051379:Mice; D008954:Models, Biological; D019913:Nuclear Localization Signals / Q000378:metabolism; D011062:Polynucleotide Adenylyltransferase / Q000737:chemistry / Q000378:metabolism*; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D039221:mRNA Cleavage and Polyadenylation Factors
D018076:DNA, Complementary; D019913:Nuclear Localization Signals; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D005982:Glutathione Transferase; D011062:Polynucleotide Adenylyltransferase