Subcellular Localization and Differentiation-Induced Redistribution of the Protein Tyrosine Phosphatase PTP-BL in Neuroblastoma Cells |
| |
Authors: | Marco?van?Ham Lottie?Kemperman Mietske?Wijers Jack?Fransen Email author" target="_blank">Wiljan?HendriksEmail author |
| |
Institution: | Department of Cell Biology, Institute of Cellular Signalling, Nijmegen Centre for Molecular Life Sciences, Radbound University Nijmegen Medical Centre, Nijmegen, The Netherlands. |
| |
Abstract: | 1.In cells of epithelial origin the protein tyrosine phosphatase PTP-BL is predominantly localized at the apical membrane of polarized cells. This large submembranous multidomain PTP is also expressed in cells of neuronal origin. We studied the localization of PTP-BL in mouse neuroblastoma cells utilizing EGFP-tagged versions of the protein. 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. Additionally, significant amounts of EGFP-PTP-BL are located in the cytoplasm as well as in nuclei. Upon serum depletion-induced differentiation of Neuro-2a cells, a partial shift of EGFP-PTP-BL from a cortical localization to cytoskeleton-like F-actin-positive structures is observed. Parallel biochemical studies corroborate this finding and reveal a serum depletion-induced shift of EFGP-PTP-BL from a membrane(-associated) fraction to an NP40-soluble cytoskeletal fraction. 3. Different pools of PTP-BL-containing protein complexes can be discerned in neuronal cells, reflecting distinct molecular microenvironments in which PTP-BL may exert its function. |
| |
Keywords: | cytoskeleton differentiation FERM domain PDZ domain redistribution |
本文献已被 PubMed SpringerLink 等数据库收录! |