5F5U

Crystal structure of the Snu23-Prp38-MFAP1(217-258) complex of Chaetomium thermophilum

Summary for 5F5U

• Entry DOI: 10.2210/pdb5f5u/pdb
• Descriptor: Prp38, Putative uncharacterized protein, Zinc finger domain-containing protein, ... (4 entities in total)
• Functional Keywords: b-specific protein, heterotrimer, pre-mrna splicing, sah, splicing
• Biological source: Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719); More
• Total number of polymer chains: 9
• Total formula weight: 119838.96

Authors

Ulrich, A.K.C.,Seeger, M.,Bartlick, N.,Wahl, M.C. (deposition date: 2015-12-04, release date: 2016-10-19, Last modification date: 2024-01-10)

Primary citation

Ulrich, A.K.C.,Seeger, M.,Schutze, T.,Bartlick, N.,Wahl, M.C.
Scaffolding in the Spliceosome via Single alpha Helices.
Structure, 24:1972-1983, 2016

PubMed Abstract: The spliceosomal B complex-specific protein Prp38 forms a complex with the intrinsically unstructured proteins MFAP1 and Snu23. Our binding and crystal structure analyses show that MFAP1 and Snu23 contact Prp38 via ER/K motif-stabilized single α helices, which have previously been recognized only as rigid connectors or force springs between protein domains. A variant of the Prp38-binding single α helix of MFAP1, in which ER/K motifs not involved in Prp38 binding were mutated, was less α-helical in isolation and showed a reduced Prp38 affinity, with opposing tendencies in interaction enthalpy and entropy. Our results indicate that the strengths of single α helix-based interactions can be tuned by the degree of helix stabilization in the unbound state. MFAP1, Snu23, and several other spliceosomal proteins contain multiple regions that likely form single α helices via which they might tether several binding partners and act as intermittent scaffolds that facilitate remodeling steps during assembly of an active spliceosome.

PubMed: 27773687
DOI: 10.1016/j.str.2016.09.007

Experimental method

X-RAY DIFFRACTION (2.748 Å)