She2p is a novel RNA binding protein with a basic helical hairpin motif.
Selective transport of mRNAs in ribonucleoprotein particles (mRNP) ensures asymmetric distribution of information within and among eukaryotic cells. Actin-dependent transport of ASH1 mRNA in yeast represents one of the best-characterized examples of mRNP translocation. Formation of the ASH1 mRNP requires recognition of zip code elements by the RNA binding protein She2p. We determined the X-ray structure of She2p at 1.95 A resolution. She2p is a member of a previously unknown class of nucleic acid binding proteins, composed of a single globular domain with a five alpha helix bundle that forms a symmetric homodimer. After demonstrating potent, dimer-dependent RNA binding in vitro, we mapped the RNA binding surface of She2p to a basic helical hairpin in vitro and in vivo and present a mechanism for mRNA-dependent initiation of ASH1 mRNP complex assembly.
Niessing
Dierk
D
Laboratories of Molecular Biophysics and The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Hüttelmaier
Stefan
S
Zenklusen
Daniel
D
Singer
Robert H
RH
Burley
Stephen K
SK
D000595:Amino Acid Sequence; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000235:genetics; D019281:Dimerization; D008958:Models, Molecular; D008969:Molecular Sequence Data; D012331:RNA, Fungal / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000737:chemistry*; D012097:Repressor Proteins / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics
C098733:ASH1 protein, S cerevisiae; D004268:DNA-Binding Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D012097:Repressor Proteins; C471175:SHE2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins