Anti-PTBP1 Antibody Picoband® (monoclonal, 3H12)

Polypyrimidine tract-binding protein 1 is a protein that in humans is encoded by the PTBP1 gene. It is mapped to 19p13.3. This gene belongs to the subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs) . The hnRNPs are RNA-binding proteins and they complex with heterogeneous nuclear RNA (hnRNA) . These proteins are associated with pre-mRNAs in the nucleus and appear to influence pre-mRNA processing and other aspects of mRNA metabolism and transport. While all of the hnRNPs are present in the nucleus, some seem to shuttle between the nucleus and the cytoplasm. The hnRNP proteins have distinct nucleic acid binding properties. The protein encoded by this gene has four repeats of quasi-RNA recognition motif (RRM) domains that bind RNAs. This protein binds to the intronic polypyrimidine tracts that requires pre-mRNA splicing and acts via the protein degradation ubiquitin-proteasome pathway. It may also promote the binding of U2 snRNP to pre-mRNAs. This protein is localized in the nucleoplasm and it is also detected in the perinucleolar structure. Alternatively spliced transcript variants encoding different isoforms have been described.

Seems to act as an adapter protein between membrane proteins and the actin cytoskeleton. In collaboration with CBLC, modulates the rate of RET turnover and may act as regulatory checkpoint that limits the potency of GDNF on neuronal survival. Controls CBLC function, converting it from an inhibitor to a promoter of RET degradation. May play a role in receptor clustering and cytoskeletal polarity in the junction between T- cell and antigen-presenting cell. May anchor the podocyte slit diaphragm to the actin cytoskeleton in renal glomerolus. Also required for cytokinesis.

1. Charlet-B., N., Logan, P., Singh, G., Cooper, T. A. Dynamic antagonism between ETR-3 and PTB regulates cell type-specific alternative splicing. Molec. Cell 9: 649-658, 2002. 2. David, C. J., Chen, M., Assanah, M., Canoll, P., Manley, J. L. HnRNP proteins controlled by c-Myc deregulate pyruvate kinase mRNA splicing in cancer. Nature 463: 364-368, 2010. 3. Ghetti, A., Pinol-Roma, S., Michael, W. M., Morandi, C., Dreyfuss, G. HNRNP I, the polypyrimidine tract-binding protein: distinct nuclear localization and association with hnRNAs. Nucleic Acids Res. 20: 3671-3678, 1992.

Store at -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freeze-thaw cycles.

Cytoplasm, cytoskeleton . Cell projection, ruffle . Colocalizes with F-actin and BCAR1/p130Cas in membrane ruffles. Located at podocyte slit diaphragm between podocyte foot processes (By similarity) . During late anaphase and telophase, concentrates in the vicinity of the midzone microtubules and in the midbody in late telophase.