Document Detail


Assembly of the SLIP1-SLBP complex on histone mRNA requires heterodimerization and sequential binding of SLBP followed by SLIP1.
MedLine Citation:
PMID:  23286197     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The SLIP1-SLBP complex activates translation of replication-dependent histone mRNAs. In this report, we describe how the activity of the SLIP1-SLBP complex is modulated by phosphorylation and oligomerization. Biophysical characterization of the free proteins shows that whereas SLIP1 is a homodimer that does not bind RNA, human SLBP is an intrinsically disordered protein that is phosphorylated at 23 Ser/Thr sites when expressed in a eukaryotic expression system such as baculovirus. The bacterially expressed unphosphorylated SLIP1-SLBP complex forms a 2:2 high-affinity (K(D) < 0.9 nM) heterotetramer that is also incapable of binding histone mRNA. In contrast, phosphorylated SLBP from baculovirus has a weak affinity (K(D) ~3 μM) for SLIP1. Sequential binding of phosphorylated SLBP to the histone mRNA stem-loop motif followed by association with SLIP1 is required to form an "active" ternary complex. Phosphorylation of SLBP at Thr171 promotes dissociation of the heterotetramer to the SLIP1-SLBP heterodimer. Using alanine scanning mutagenesis, we demonstrate that the binding site on SLIP1 for SLBP lies close to the dimer interface. A single-point mutant near the SLIP1 homodimer interface abolished interaction with SLBP in vitro and reduced the abundance of histone mRNA in vivo. On the basis of these biophysical studies, we propose that oligomerization and SLBP phosphorylation may regulate the SLBP-SLIP1 complex in vivo. SLIP1 may act to sequester SLBP in vivo, protecting it from proteolytic degradation as an inactive heterotetramer, or alternatively, formation of the SLIP1-SLBP heterotetramer may facilitate removal of SLBP from the histone mRNA prior to histone mRNA degradation.
Authors:
Nitin Bansal; Minyou Zhang; Aishwarya Bhaskar; Patrick Itotia; EunHee Lee; Lyudmila S Shlyakhtenko; TuKiet T Lam; Andrew Fritz; Ronald Berezney; Yuri L Lyubchenko; Walter F Stafford; Roopa Thapar
Related Documents :
9831247 - Cooperative binding and synergistic activation by rela and c/ebpbeta on the intercellul...
7523527 - Measurement of mrna for e-selectin, vcam-1 and icam-1 by reverse transcription and the ...
9594207 - Significance of p-selectin expression in human glomerulonephritis.
1691227 - Preferential expression of the complement regulatory protein decay accelerating factor ...
23189187 - Inhibition of pten gene expression by oncogenic mir-23b-3p in renal cancer.
12241077 - Control analysis of dna microarray expression data.
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't     Date:  2013-01-11
Journal Detail:
Title:  Biochemistry     Volume:  52     ISSN:  1520-4995     ISO Abbreviation:  Biochemistry     Publication Date:  2013 Jan 
Date Detail:
Created Date:  2013-01-22     Completed Date:  2013-03-14     Revised Date:  2014-01-24    
Medline Journal Info:
Nlm Unique ID:  0370623     Medline TA:  Biochemistry     Country:  United States    
Other Details:
Languages:  eng     Pagination:  520-36     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Carrier Proteins / chemistry*,  genetics,  metabolism*
Histones / chemistry,  genetics,  metabolism*
Humans
Kinetics
Mutagenesis, Site-Directed
Mutant Proteins / chemistry,  metabolism
Nuclear Proteins / chemistry*,  genetics,  metabolism*
Peptide Fragments / chemistry,  genetics,  metabolism
Phosphorylation
Point Mutation
Protein Binding
Protein Interaction Domains and Motifs
Protein Multimerization
Protein Processing, Post-Translational
RNA Folding
RNA, Messenger / chemistry*,  metabolism*
Recombinant Proteins / chemistry,  metabolism
Serine / chemistry,  metabolism
Threonine / chemistry,  metabolism
Tyrosine / chemistry,  metabolism
mRNA Cleavage and Polyadenylation Factors / chemistry*,  genetics,  metabolism*
Grant Support
ID/Acronym/Agency:
1P01-GM091743/GM/NIGMS NIH HHS; 1R01-GM072131/GM/NIGMS NIH HHS; 1R01-GM076660/GM/NIGMS NIH HHS; 1R01-GM076660-04S1/GM/NIGMS NIH HHS; 1R01-GM096039/GM/NIGMS NIH HHS; R01 GM076660/GM/NIGMS NIH HHS; R01 GM096039/GM/NIGMS NIH HHS; UL1 TR000142/TR/NCATS NIH HHS
Chemical
Reg. No./Substance:
0/Carrier Proteins; 0/Histones; 0/Mutant Proteins; 0/Nuclear Proteins; 0/Peptide Fragments; 0/RNA, Messenger; 0/Recombinant Proteins; 0/SLBP protein, human; 0/SLIP1 protein, human; 0/mRNA Cleavage and Polyadenylation Factors; 2ZD004190S/Threonine; 42HK56048U/Tyrosine; 452VLY9402/Serine
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Discovery of 5-Benzyl-3-phenyl-4,5-dihydroisoxazoles and 5-Benzyl-3-phenyl-1,4,2-dioxazoles as Poten...
Next Document:  Using Binary Surfactant Mixtures to Simultaneously Improve Dimensional Tunability and Monodispersity...