PTBP-2 is a member of the polypyrimidine tract binding family of proteins. Predominantly expressed in brain, but also found in heart and skeletal muscle, PTBP-2 localizes to the nucleus and contains four RRM (RNA recognition motif) domains. PTBP-2 functions as an RNA-binding protein associated in a complex that is involved in the regulation of exon splicing and the stabilization of mRNAs in the cytoplasm. Six isoforms exist for PTBP-2 due to alternative splicing events. Isoforms 1 and 2 (al