A highly conserved RNA-binding protein for cytoplasmic mRNA localization in vertebrates.
BACKGROUND
Cytoplasmic mRNA localization is a widespread mechanism for restricting the translation of specific mRNAs to distinct regions of eucaryotic cells. This process involves specific interactions between cellular factors and localization signals in the 3' untranslated regions of the localized mRNA. Because only a few of these cellular factors have been identified, it is not known whether common factors are utilized for the localization of different mRNAs. We recently discovered Vera, a protein that binds specifically to the Vg1 localization element and is involved in the localization of Vg1 mRNA in Xenopus oocytes.


RESULTS
To characterize further the role of Vera in the localization of Vg1 mRNA, we have purified the Vera protein and cloned its gene. Vera is homologous to chicken zip-code-binding protein (ZBP), which binds to a short RNA sequence required for localization of beta-actin mRNA in chick embryo fibroblasts. The predicted amino-acid sequences of Vera and ZBP contain five RNA-binding domains and putative signals for nuclear localization and export. Like the binding of ZBP to beta-actin mRNA, Vera specifically binds to a repeated sequence motif in the Vg1 localization element that is required for Vg1 mRNA localization in Xenopus oocytes.


CONCLUSIONS
Vera, a highly conserved component of the mRNA localization machinery, participates in localizing different mRNAs in different cell types. Thus, Vera appears to be a general factor for mRNA localization, and additional factors may be required to specify diverse patterns of RNA localization.
Deshler
J O
JO
Department of Cell Biology Harvard Medical School 240 Longwood Avenue, Boston, Massachusetts, 02115, USA.
Highett
M I
MI
Abramson
T
T
Schnapp
B J
BJ
D000595:Amino Acid Sequence; D000818:Animals; D030161:Avian Proteins; D002645:Chickens; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D009183:Mycotoxins; D009865:Oocytes / Q000737:chemistry; D010088:Oxidoreductases; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D014981:Xenopus; D029867:Xenopus Proteins
D030161:Avian Proteins; D005656:Fungal Proteins; C498635:IGF2BP3 protein, Xenopus; D009183:Mycotoxins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029867:Xenopus Proteins; C498636:ZBP1 protein, Gallus gallus; D010088:Oxidoreductases; C088000:STCU protein, Emericella nidulans