5DCA

Crystal structure of yeast full length Brr2 in complex with Prp8 Jab1 domain

Summary for 5DCA

• Entry DOI: 10.2210/pdb5dca/pdb
• Descriptor: Pre-mRNA-splicing helicase BRR2, Pre-mRNA-splicing factor 8 (3 entities in total)
• Functional Keywords: protein complex, helicase, rnp remodeling, spliceosome activation, hydrolase
• Biological source: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast); More
• Cellular location: Nucleus : P32639 P33334
• Total number of polymer chains: 2
• Total formula weight: 250657.74

Authors

Absmeier, E.,Wollenhaupt, J.,Santos, K.F.,Wahl, M.C. (deposition date: 2015-08-23, release date: 2015-12-16, Last modification date: 2024-01-10)

Primary citation

Absmeier, E.,Wollenhaupt, J.,Mozaffari-Jovin, S.,Becke, C.,Lee, C.T.,Preussner, M.,Heyd, F.,Urlaub, H.,Luhrmann, R.,Santos, K.F.,Wahl, M.C.
The large N-terminal region of the Brr2 RNA helicase guides productive spliceosome activation.
Genes Dev., 29:2576-2587, 2015

PubMed Abstract: The Brr2 helicase provides the key remodeling activity for spliceosome catalytic activation, during which it disrupts the U4/U6 di-snRNP (small nuclear RNA protein), and its activity has to be tightly regulated. Brr2 exhibits an unusual architecture, including an ∼ 500-residue N-terminal region, whose functions and molecular mechanisms are presently unknown, followed by a tandem array of structurally similar helicase units (cassettes), only the first of which is catalytically active. Here, we show by crystal structure analysis of full-length Brr2 in complex with a regulatory Jab1/MPN domain of the Prp8 protein and by cross-linking/mass spectrometry of isolated Brr2 that the Brr2 N-terminal region encompasses two folded domains and adjacent linear elements that clamp and interconnect the helicase cassettes. Stepwise N-terminal truncations led to yeast growth and splicing defects, reduced Brr2 association with U4/U6•U5 tri-snRNPs, and increased ATP-dependent disruption of the tri-snRNP, yielding U4/U6 di-snRNP and U5 snRNP. Trends in the RNA-binding, ATPase, and helicase activities of the Brr2 truncation variants are fully rationalized by the crystal structure, demonstrating that the N-terminal region autoinhibits Brr2 via substrate competition and conformational clamping. Our results reveal molecular mechanisms that prevent premature and unproductive tri-snRNP disruption and suggest novel principles of Brr2-dependent splicing regulation.

PubMed: 26637280
DOI: 10.1101/gad.271528.115

Experimental method

X-RAY DIFFRACTION (2.8 Å)