Polypyrimidine tract binding protein

Anwar, A., Ali, N., Tanveer, R. and Siddiqui, A. (2000) Demonstration of functional requirement of polypyrimidine tract-binding protein by SELEX RNA during hepatitis C virus internal ribosome entry site-mediated translation initiation. J. Biol. Chem., 275, 34231-34235. 

Singh, R., Valcarcel, J. and Green, M.R. (1995) Distinct binding specificities and functions of higher eukaryotic polypyrimidine tract-binding proteins. Science, 268,1173-1176. 

In a patient with congenital myasthenic syndrome, we identified that CHRNAl IVS3-8G>A attenuates binding of hnRNP /f 100-fold and causes exclusive inclusion of the downstream exon P3A (Masuda et al., 2008) (Fig. 4). We also identified that polypyrimidine tract binding protein (PTB) silences recognition of exon P3A and tannic acid facilitates the expression of PTB by activating its promoter region (Gao et al., 2009). 

Polypyrimidine tract-binding protein, a repressive regulator of protein splicing also pulmonary tuberculosis Protein transduction domain... 

Fig. 4.1. Mobility shift analysis Mobility shift analysis performed by 4% PAGE in 50 mM Tris-glycine 1 mM EDTA. The mobility shift is induced by the 60 kD polypyrimidine tract binding protein to a 220 nucleotide random labelled pre-mRNA transcript. The experiment shows dimeric binding (2. complex) of the protein at...

Fig. 4.5. Mg2+-dependence of the identity of UV cross-linked proteins. A randomly labelled 5 untranslated region from a growth factor mRNA was mixed with a cytoplasmic lysate at increasing Mg2+ concentrations in the binding buffer, and UV cross-linking was carried out as described in the text. PTB is the polypyrimidine tract binding protein, p50 is the major core protein of mRNPs, and p69 is a leader-specific binding protein.

The widespread occurrence of polypurine polypyrimidine tracts in eukaryotic DNA suggests that these sequences may have a biological function. Analysis of eukaryotic sequence databases reveals thousands of polypurine polypyrimidine tracts, many with the potential for triplex formation. These polypurine regions of DNA can potentially influence biology in several ways. They could provide binding sites for regulatory proteins, influ-... 

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