1h6k
From Proteopedia
NUCLEAR CAP BINDING COMPLEX
Overview
The heterodimeric nuclear cap binding complex (CBC) binds to 5'-capped polymerase II transcripts. It enhances the efficiency of several mRNA maturation steps and is essential for U snRNA nuclear export in multicellular eukaryotes. The 2A crystal structure of human CBC shows that the large subunit, CBP80, comprises three domains, each containing consecutive helical hairpins and resembling the so-called MIF4G domain found in several other proteins involved in RNA metabolism. The small subunit, CPB20, has an RNP fold and associates with the second and third domains of CBP80. Site-directed mutagenesis revealed 4 residues of CBP20 which are critical for cap binding. A model for cap binding is proposed based on these results and the known mode of binding of RNA to RNP domains.
About this Structure
1H6K is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of the human nuclear cap binding complex., Mazza C, Ohno M, Segref A, Mattaj IW, Cusack S, Mol Cell. 2001 Aug;8(2):383-96. PMID:11545740 Page seeded by OCA on Fri May 2 18:29:55 2008
