Homodimerization of the human U1 snRNP-specific protein C

• Published in: Nucleic acids research Vol. 23; no. 23; pp. 4864 - 4871
• Main Authors: Klein Gunnewiek, Jacqueline M.T., van Aarssen, Yvonne, Wassenaar, Roel, Legrain, Pierre, van Venrooij, Walther J., Nelissen, Rob L.H.
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 11-12-1995
• Subjects: Electrophoresis, Polyacrylamide Gel; Escherichia coli; HeLa Cells; Humans; Mutagenesis, Site-Directed; Protein Biosynthesis; Protein C - chemistry; Protein C - isolation & purification; Protein C - metabolism; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - isolation & purification; Recombinant Fusion Proteins - metabolism; Ribonucleoprotein, U1 Small Nuclear - chemistry; Ribonucleoprotein, U1 Small Nuclear - metabolism; Zinc Fingers
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/23.23.4864

The U1 snRNP-specific protein C contains an N-terminal zinc finger-like CH motif which Is required for the binding of the U1C protein to the U1 snRNP particle. Recently a similar motif was reported to be essential for in vivo homodimerization of the yeast splicing factor PRP9. In the present study we demonstrate that the human U1C protein is able to form homodimers as well. U1C homodimers are found when (i) the human U1C protein is expressed in Escherlchia coli, (II) immunoprecipitations with anti-U1C antibodies are performed on in vitro translated U1C, and when (iii) the yeast two hybrid system Is used. Analyses of mutant U1C proteins in an in vitro dimerization assay and the yeast two hybrid system revealed that amlno acids within the CH motif, i.e. between positions 22 and 30, are required for homodimerization.