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Title: Structure and Interactions of the CS Domain of Human H/ACA RNP Assembly Protein Shq1

Shq1 is an essential protein involved in the early steps of biogenesis and assembly of H/ACA ribonucleoprotein particles (RNPs). Shq1 binds to dyskerin (Cbf5 in yeast) at an early step of H/ACA RNP assembly and is subsequently displaced by the H/ACA RNA. Shq1 contains an N-terminal CS and a C-terminal Shq1-specific domain (SSD). Dyskerin harbors many mutations associated with dyskeratosis congenita. Structures of yeast Shq1 SSD bound to Cbf5 revealed that only a subset of these mutations is in the SSD binding site, implicating another subset in the putative CS binding site. Here in this paper, we present the crystal structure of human Shq1 CS (hCS) and the nuclear magnetic resonance (NMR) and crystal structures of hCS containing a serine substitution for proline 22 that is associated with some prostate cancers. The structure of hCS is similar to yeast Shq1 CS domain (yCS) and consists of two β-sheets that form an immunoglobulin-like β-sandwich fold. The N-terminal affinity tag sequence AHHHHHH associates with a neighboring protein in the crystal lattice to form an extra β-strand. Deletion of this tag was required to get spectra suitable for NMR structure determination, while the tag was required for crystallization. NMR chemical shift perturbation (CSP)more » experiments with peptides derived from putative CS binding sites on dyskerin and Cbf5 revealed a conserved surface on CS important for Cbf5/dyskerin binding. A HADDOCK (high-ambiguity-driven protein-protein docking) model of a Shq1-Cbf5 complex that defines the position of CS domain in the pre-H/ACA RNP was calculated using the CSP data.« less
Authors:
 [1] ;  [2] ;  [3] ;  [4]
  1. Univ. of California, Los Angeles, CA (United States). Dept. of Chemistry and Biochemistry; Indian Inst. of Science, Bangalore (India)
  2. Univ. of California, Los Angeles, CA (United States). Dept. of Chemistry and Biochemistry; Univ. of Texas, San Antonio, TX (United States). Dept. of Biochemistry
  3. Univ. of California, Los Angeles, CA (United States). Inst. for Genomics and Proteomics
  4. Univ. of California, Los Angeles, CA (United States). Dept. of Chemistry and Biochemistry; Univ. of California, Los Angeles, CA (United States). Inst. for Genomics and Proteomics
Publication Date:
OSTI Identifier:
1170018
Grant/Contract Number:
FC0302ER63421; AC02-06CH11357; P41 RR015301; P41 GM103403; MCB1022379; GM048123
Type:
Accepted Manuscript
Journal Name:
Journal of Molecular Biology
Additional Journal Information:
Journal Volume: 427; Journal Issue: 4; Journal ID: ISSN 0022-2836
Publisher:
Elsevier
Research Org:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org:
National Institutes of Health (NIH); USDOE; National Science Foundation (NSF)
Country of Publication:
United States
Language:
ENGLISH
Subject:
60 APPLIED LIFE SCIENCES; NMR; chemical shift perturbation; X-ray crystal structure; dyskerin and Cbf5; telomerase