A Xenopus Protein Related to hnRNP I Has a Role in Cytoplasmic RNA Localization

• Published in: Molecular cell Vol. 4; no. 3; pp. 431 - 437
• Main Authors: Cote, Colette A, Gautreau, Denise, Denegre, James M, Kress, Tracy L, Terry, Natalie A, Mowry, Kimberly L
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-09-1999
• Subjects: 3' Untranslated Regions; Animals; Biological Transport; Cell Compartmentation; Cell Polarity; Cloning, Molecular; Cytoplasm - chemistry; Freshwater; Glycoproteins - genetics; hnRNP I protein; Molecular Sequence Data; Mutation; Nuclear Proteins - genetics; Nuclear Proteins - isolation & purification; Nuclear Proteins - metabolism; Oocytes - chemistry; Polypyrimidine Tract-Binding Protein; Protein Binding; Ribonucleoproteins - genetics; Ribonucleoproteins - isolation & purification; Ribonucleoproteins - metabolism; RNA, Messenger - isolation & purification; RNA, Messenger - metabolism; RNA-Binding Proteins - genetics; RNA-Binding Proteins - isolation & purification; RNA-Binding Proteins - metabolism; Transforming Growth Factor beta; VgRBP60 protein; Xenopus; Xenopus Proteins
• ISSN: 1097-2765; 1097-4164
• DOI: 10.1016/S1097-2765(00)80345-7

Cytoplasmic localization of mRNA molecules is a powerful mechanism for generating cell polarity. In vertebrates, one paradigm is localization of Vg1 RNA within the
Xenopus oocyte, a process directed by recognition of a localization element within the Vg1 3′ UTR. We show that specific base changes within the localization element abolish both localization in vivo and binding in vitro by a single protein, VgRBP60. VgRBP60 is homologous to a human hnRNP protein, hnRNP I, and combined immunolocalization and in situ hybridization demonstrate striking colocalization of hnRNP I and Vg1 RNA within the vegetal cytoplasm of the
Xenopus oocyte. These results implicate a novel role in cytoplasmic RNA transport for this family of nuclear RNA-binding proteins.