New Insights into Functional Roles of the Polypyrimidine Tract-Binding Protein

International Journal of Molecular Sciences

Maria Grazia Romanelli¹  Erica Diani² 

[1] Department of Life and Reproduction Sciences, Section of Biology and Genetics, University of Verona, Strada Le Grazie 8, 37134 Verona, Italy;

关键词: PTB;    raver1;    alternative splicing;    IRES;    RRM;    RNA binding proteins;    ribonucleoproteins;    hnRNP;    mRNA stability;    cell differentiation;   

DOI  :  10.3390/ijms141122906

来源: mdpi

【 摘 要 】

Polypyrimidine Tract Binding Protein (PTB) is an intensely studied RNA binding protein involved in several post-transcriptional regulatory events of gene expression. Initially described as a pre-mRNA splicing regulator, PTB is now widely accepted as a multifunctional protein shuttling between nucleus and cytoplasm. Accordingly, PTB can interact with selected RNA targets, structural elements and proteins. There is increasing evidence that PTB and its paralog PTBP2 play a major role as repressors of alternatively spliced exons, whose transcription is tissue-regulated. In addition to alternative splicing, PTB is involved in almost all steps of mRNA metabolism, including polyadenylation, mRNA stability and initiation of protein translation. Furthermore, it is well established that PTB recruitment in internal ribosome entry site (IRES) activates the translation of picornaviral and cellular proteins. Detailed studies of the structural properties of PTB have contributed to our understanding of the mechanism of RNA binding by RNA Recognition Motif (RRM) domains. In the present review, we will describe the structural properties of PTB, its paralogs and co-factors, the role in post-transcriptional regulation and actions in cell differentiation and pathogenesis. Defining the multifunctional roles of PTB will contribute to the understanding of key regulatory events in gene expression.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland