3HIB

Crystal structure of the second Sec63 domain of yeast Brr2

Summary for 3HIB

• Entry DOI: 10.2210/pdb3hib/pdb
• Descriptor: Pre-mRNA-splicing helicase BRR2 (2 entities in total)
• Functional Keywords: rna helicase, atp-binding, helicase, mrna processing, mrna splicing, nucleotide-binding, nucleus, spliceosome, hydrolase
• Biological source: Saccharomyces cerevisiae (yeast)
• Cellular location: Nucleus (Potential): P32639
• Total number of polymer chains: 1
• Total formula weight: 36278.67

Authors

Zhang, L.,Xu, T.,Zhao, R. (deposition date: 2009-05-19, release date: 2009-06-16, Last modification date: 2011-07-13)

Primary citation

Zhang, L.,Xu, T.,Maeder, C.,Bud, L.O.,Shanks, J.,Nix, J.,Guthrie, C.,Pleiss, J.A.,Zhao, R.
Structural evidence for consecutive Hel308-like modules in the spliceosomal ATPase Brr2.
Nat.Struct.Mol.Biol., 16:731-739, 2009

PubMed Abstract: Brr2 is a DExD/H-box helicase responsible for U4/U6 unwinding during spliceosomal activation. Brr2 contains two helicase-like domains, each of which is followed by a Sec63 domain with unknown function. We determined the crystal structure of the second Sec63 domain, which unexpectedly resembles domains 4 and 5 of DNA helicase Hel308. This, together with sequence similarities between Brr2's helicase-like domains and domains 1-3 of Hel308, led us to hypothesize that Brr2 contains two consecutive Hel308-like modules (Hel308-I and Hel308-II). Our structural model and mutagenesis data suggest that Brr2 shares a similar helicase mechanism with Hel308. We demonstrate that Hel308-II interacts with Prp8 and Snu114 in vitro and in vivo. We further find that the C-terminal region of Prp8 (Prp8-CTR) facilitates the binding of the Brr2-Prp8-CTR complex to U4/U6. Our results have important implications for the mechanism and regulation of Brr2's activity in splicing.

PubMed: 19525970
DOI: 10.1038/nsmb.1625

Experimental method

X-RAY DIFFRACTION (2 Å)