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Title: Structural Basis for Polypyrimidine Tract Recognition by the Essential Pre-mRNA Splicing Factor U2AF65

Abstract

The essential pre-mRNA splicing factor, U2AF{sup 65}, guides the early stages of splice site choice by recognizing a polypyrimidine (Py)-tract consensus sequence near the 3'-splice site. Since Py-tracts are relatively poorly conserved in higher eukaryotes, U2AF{sup 65} is faced with the problem of specifying uridine-rich sequences, yet tolerating a variety of nucleotide substitutions found in natural Py-tracts. To better understand these apparently contradictory RNA binding characteristics, the X-ray structure of the U2AF{sup 65} RNA binding domain bound to a Py-tract composed of seven uridines has been determined at 2.5Angstroms resolution. Specific hydrogen bonds between U2AF{sup 65} and the uracil bases provide an explanation for polyuridine recognition. Flexible sidechains and bound water molecules form the majority of the base contacts, and potentially could rearrange when the U2AF{sup 65} structure adapts to different Py-tract sequences. The energetic importance of conserved residues for Py-tract binding is established by analysis of site-directed mutant U2AF{sup 65} proteins using surface plasmon resonance.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
914077
Report Number(s):
BNL-78645-2007-JA
TRN: US0801524
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Mol. Cell; Journal Volume: 23; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; 43 PARTICLE ACCELERATORS; HYDROGEN; MUTANTS; NUCLEOTIDES; PLASMONS; PROTEINS; RESIDUES; RESOLUTION; RESONANCE; RNA; SPLICING; URACILS; WATER; NSLS; national synchrotron light source

Citation Formats

Sickmier,E., Frato, K., Shen, H., Paranawithana, S., Green, M., and Kielkopf, C. Structural Basis for Polypyrimidine Tract Recognition by the Essential Pre-mRNA Splicing Factor U2AF65. United States: N. p., 2006. Web. doi:10.1016/j.molcel.2006.05.025.
Sickmier,E., Frato, K., Shen, H., Paranawithana, S., Green, M., & Kielkopf, C. Structural Basis for Polypyrimidine Tract Recognition by the Essential Pre-mRNA Splicing Factor U2AF65. United States. doi:10.1016/j.molcel.2006.05.025.
Sickmier,E., Frato, K., Shen, H., Paranawithana, S., Green, M., and Kielkopf, C. Sun . "Structural Basis for Polypyrimidine Tract Recognition by the Essential Pre-mRNA Splicing Factor U2AF65". United States. doi:10.1016/j.molcel.2006.05.025.
@article{osti_914077,
title = {Structural Basis for Polypyrimidine Tract Recognition by the Essential Pre-mRNA Splicing Factor U2AF65},
author = {Sickmier,E. and Frato, K. and Shen, H. and Paranawithana, S. and Green, M. and Kielkopf, C.},
abstractNote = {The essential pre-mRNA splicing factor, U2AF{sup 65}, guides the early stages of splice site choice by recognizing a polypyrimidine (Py)-tract consensus sequence near the 3'-splice site. Since Py-tracts are relatively poorly conserved in higher eukaryotes, U2AF{sup 65} is faced with the problem of specifying uridine-rich sequences, yet tolerating a variety of nucleotide substitutions found in natural Py-tracts. To better understand these apparently contradictory RNA binding characteristics, the X-ray structure of the U2AF{sup 65} RNA binding domain bound to a Py-tract composed of seven uridines has been determined at 2.5Angstroms resolution. Specific hydrogen bonds between U2AF{sup 65} and the uracil bases provide an explanation for polyuridine recognition. Flexible sidechains and bound water molecules form the majority of the base contacts, and potentially could rearrange when the U2AF{sup 65} structure adapts to different Py-tract sequences. The energetic importance of conserved residues for Py-tract binding is established by analysis of site-directed mutant U2AF{sup 65} proteins using surface plasmon resonance.},
doi = {10.1016/j.molcel.2006.05.025},
journal = {Mol. Cell},
number = 1,
volume = 23,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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