Protein: Polypyrimidine tract-binding protein 1 (PTB) (57 kDa RNA-binding protein PPTB-1) (Heterogeneous nuclear ribonucleoprotein I) (hnRNP I) (P26599)
Organism: Homo sapiens (Human)
Function: Plays a role in pre-mRNA splicing and in the regulation of alternative splicing events. Activates exon skipping of its own pre-mRNA during muscle cell differentiation. Binds to the polypyrimidine tract of introns. May promote RNA looping when bound to two separate polypyrimidine tracts in the same pre-mRNA. May promote the binding of U2 snRNP to pre-mRNA. Cooperates with RAVER1 to modulate switching between mutually exclusive exons during maturation of the TPM1 pre-mRNA. Represses the splicing of MAPT/Tau exon 10. Binds to polypyrimidine-rich controlling element (PCE) of CFTR and promotes exon skipping of CFTR exon 9, thereby antagonizing TIA1 and its role in exon inclusion of CFTR exon 9. Plays a role in the splicing of pyruvate kinase PKM by binding repressively to a polypyrimidine tract flanking PKM exon 9, inhibiting exon 9 inclusion and resulting in exon 10 inclusion and production of the PKM M2 isoform. In case of infection by picornaviruses, binds to the viral internal ribosome entry site (IRES) and stimulates the IRES-mediated translation.
Subcellular location: Nucleus.
Sequence: MDGIVPDIAVGTKRGSDELFSTCVTNGPFIMSSNSASAANGNDSKKFKGDSRSAGVPSRVIHIRKLPIDVTEGEVISLGLPFGKVTNLLMLKGKNQAFIEMNTEEAANTMVNYYTSVTPVLRGQPIYIQFSNHKELKTDSSPNQARAQAALQAVNSVQSGNLALAASAAAVDAGMAMAGQSPVLRIIVENLFYPVTLDVLHQIFSKFGTVLKIITFTKNNQFQALLQYADPVSAQHAKLSLDGQNIYNACCTLRIDFSKLTSLNVKYNNDKSRDYTRPDLPSGDSQPSLDQTMAAAFGAPGIISASPYAGAGFPPTFAIPQAAGLSVPNVHGALAPLAIPSAAAAAAAAGRIAIPGLAGAGNSVLLVSNLNPERVTPQSLFILFGVYGDVQRVKILFNKKENALVQMADGNQAQLAMSHLNGHKLHGKPIRITLSKHQNVQLPREGQEDQGLTKDYGNSPLHRFKKPGSKNFQNIFPPSATLHLSNIPPSVSEEDLKVLFSSNGGVVKGFKFFQKDRKMALIQMGSVEEAVQALIDLHNHDLGENHHLRVSFSKSTI
InterPro domains: - IPR035979: RNA-binding domain superfamily (homologous_superfamily) [47-555]
- IPR012677: Nucleotide-binding alpha-beta plait domain superfamily (homologous_superfamily) [41-557]
- IPR006536: HnRNP-L/PTB (family) [57-557]
- IPR021790: PTBP1-like, RNA recognition motif 2 (domain) [178-258]
- IPR035001: PTBP1, RNA recognition motif 3 (domain) [364-456]
- IPR035000: PTBP1, RNA recognition motif 1 (domain) [59-139]
- IPR000504: RNA recognition motif domain (domain) [59-555]
Interaction partners: - Heterogeneous nuclear ribonucleoprotein A1
- Heterogeneous nuclear ribonucleoprotein K
- Heterogeneous nuclear ribonucleoproteins C1/C2
- Heterogeneous nuclear ribonucleoprotein L
- Heterogeneous nuclear ribonucleoproteins A2/B1
- Serine/arginine-rich splicing factor 1
- Heterogeneous nuclear ribonucleoprotein M
- Heterogeneous nuclear ribonucleoprotein H
- Poly
- Splicing factor, proline- and glutamine-rich
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0097159 (organic cyclic compound binding), GO:1901363 (heterocyclic compound binding), GO:0003676 (nucleic acid binding), GO:0003723 (RNA binding)
Biological Process (BP): GO:0008150 (biological process), GO:0032502 (developmental process), GO:0065007 (biological regulation), GO:0050789 (regulation of biological process), GO:0048519 (negative regulation of biological process), GO:0009892 (negative regulation of metabolic process), GO:0048856 (anatomical structure development), GO:0009653 (anatomical structure morphogenesis), GO:0019222 (regulation of metabolic process), GO:0048523 (negative regulation of cellular process), GO:0050794 (regulation of cellular process), GO:0060255 (regulation of macromolecule metabolic process), GO:0031323 (regulation of cellular metabolic process), GO:0051172 (negative regulation of nitrogen compound metabolic process), GO:0080090 (regulation of primary metabolic process), GO:0031324 (negative regulation of cellular metabolic process), GO:0010605 (negative regulation of macromolecule metabolic process), GO:0051171 (regulation of nitrogen compound metabolic process), GO:0019219 (regulation of nucleobase-containing compound metabolic process), GO:0051252 (regulation of RNA metabolic process), GO:0051253 (negative regulation of RNA metabolic process), GO:0045934 (negative regulation of nucleobase-containing compound metabolic process), GO:0010629 (negative regulation of gene expression), GO:0010468 (regulation of gene expression), GO:0043484 (regulation of RNA splicing), GO:0033119 (negative regulation of RNA splicing)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0031974 (membrane-enclosed lumen), GO:0005654 (nucleoplasm), GO:0043229 (intracellular organelle), GO:0043233 (organelle lumen), GO:0043227 (membrane-bounded organelle), GO:0043231 (intracellular membrane-bounded organelle), GO:0070013 (intracellular organelle lumen), GO:0031981 (nuclear lumen), GO:0005634 (nucleus)