Molecular cloning of a mouse epithelial protein-tyrosine phosphatase with similarities to submembranous proteins

J Cell Biochem. 1995 Dec;59(4):418-30. doi: 10.1002/jcb.240590403.


Protein-tyrosine phosphatases (PTPases) form an important class of cell regulatory proteins. We have isolated overlapping cDNA clones that together comprise an 8 kb transcript encoding a novel murine PTPase which is expressed in various organs. Sequence analysis revealed an open reading frame of 2,460 amino acid residues. The predicted protein, PTP-BL, is a large non-transmembrane PTPase that exhibits 80% homology with PTP-BAS, a recently described human PTPase. PTP-BL shares some intriguing sequence homologies with submembranous proteins. It contains a band 4.1-like motif also present in the tumor suppressors neurofibromatosis 2 and expanded, five 80 amino acid repeats also present in the discs-large tumor suppressor, and a single catalytic phosphatase domain. No obvious homologies to other proteins were found for the N-terminal region of the protein other than human PTP-BAS. RNA in situ hybridization experiments show that the PTP-BL gene is expressed in epithelial cells, predominantly in kidney, lung, and skin. 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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA, Complementary / isolation & purification*
  • Epithelium / enzymology
  • Genetic Code
  • Humans
  • Mice
  • Molecular Sequence Data
  • Protein Tyrosine Phosphatases / genetics*
  • Sequence Homology, Amino Acid


  • DNA, Complementary
  • Protein Tyrosine Phosphatases

Associated data

  • GENBANK/Z32740