Disease relevance of Ptpn13

• To test for functional conservation of any indirect involvement of PTP-BL in Fas-mediated signaling, we generated T lymphoma cell lines stably expressing mouse or human Fas receptor with and without PTP-BL [1].
• Subcellular localization and differentiation-induced redistribution of the protein tyrosine phosphatase PTP-BL in Neuroblastoma cells [2].

High impact information on Ptpn13

• EphrinB phosphorylation and reverse signaling: regulation by Src kinases and PTP-BL phosphatase [3].
• With delayed kinetics, ephrinB ligands recruit the cytoplasmic PDZ domain containing protein tyrosine phosphatase PTP-BL and are dephosphorylated [3].
• No inhibitory effect of PTP-BL was observed upon triggering apoptosis using mouse or human Fas-activating antibodies [1].
• The Adenomatous Polyposis Coli-protein (APC) interacts with the protein tyrosine phosphatase PTP-BL via an alternatively spliced PDZ domain [4].
• The PDZ domains of the protein tyrosine phosphatase PTP-BL mediate interactions by binding to specific amino acid sequences in target proteins [5].

Biological context of Ptpn13

• PTP-BL shares some intriguing sequence homologies with submembranous proteins [6].
• The gene (PTPN13) encoding the protein tyrosine phosphatase PTP-BL/PTP-BAS is located in mouse chromosome region 5E/F and human chromosome region 4q21 [7].
• Although PTP-BL is expressed in most hematopoietic cell lineages, no alterations of thymocyte development in PTP-BL(DeltaP/DeltaP) mice could be detected [8].
• Finally, PTP-BL has been shown to be involved in the regulation of cytokinesis, the last step in cell division [9].

Anatomical context of Ptpn13

• PTP-BL phosphatase deficiency did not affect retinal ganglion cell survival in retinal cultures from lens-lesioned mice, though activated retinal glia numbers were significantly reduced in cultures from lens-lesioned PTP-BLDeltaP mice compared to lens-lesioned wildtypes [10].
• These data suggest a cell cortical localization for PTP-BL in epithelial cells and a possible role in the morphology and motility of epithelial tissues [6].
• The change of PTP36 expression level along with T cell maturation suggests its involvement in the regulation of T cell development [11].
• Here we report the cDNA cloning of a non-receptor type protein tyrosine phosphatase, PTP36, which is expressed in murine thymus [11].

Associations of Ptpn13 with chemical compounds

• Our findings exclude an essential role for PTP-BL as a phosphotyrosine phosphatase and rather are in line with a role as scaffolding or anchoring molecule [8].

Physical interactions of Ptpn13

• Cloning and characterization of mCRIP2, a mouse LIM-only protein that interacts with PDZ domain IV of PTP-BL [12].

Other interactions of Ptpn13

• These observations suggest that LAR enhances retinal ganglion cell neurite initiation whilst suppressing retinal ganglion cell survival, and that PTP-BL facilitates both retinal ganglion cell neurite initiation and survival of activated retinal glia [10].
• In addition, we found a putative SH3-binding motif in PTP36 but not in MEG-01 or PTPH1 [11].
• Here we describe a novel interaction between the APC protein and the protein tyrosine phosphatase PTP-BL carrying five PDZ protein-protein interaction domains [4].

Analytical, diagnostic and therapeutic context of Ptpn13

• RNA in situ hybridization experiments show that the PTP-BL gene is expressed in epithelial cells, predominantly in kidney, lung, and skin [6].
• 2. In proliferating Neuro-2a cells, immunofluorescence and immuno-electron microscopy revealed a submembranous FERM domain-dependent localization at cell-cell boundaries for EGFP-PTP-BL [2].
• NMR titration experiments and site-directed mutagenesis indicate that this result is not dependent on specific interactions that require surface exposed residues on the RIL LIM domain, suggesting a stabilizing role in the association with PTP-BL [13].

References