Alternative titles; symbols
HGNC Approved Gene Symbol: PTPRM
Cytogenetic location: 18p11.23 Genomic coordinates (GRCh38): 18:7,567,316-8,406,856 (from NCBI)
Gebbink et al. (1991) isolated a mouse cDNA of 5.7 kb, encoding a 'new' member of the family of receptor-like protein-tyrosine phosphatases, termed RPTP-mu. The cDNA predicted a protein of 1,432 amino acids (not including the signal peptide) with a calculated molecular mass of 161,636 Da. In addition, they cloned the human homolog, which showed 98.7% amino acid identity to the mouse protein. The predicted mouse protein consisted of a 722-amino acid extracellular region, containing 13 potential N-glycosylation sites, a single transmembrane domain, and a 688-amino acid intracellular part containing 2 tandem repeats homologous to the catalytic domains of other tyrosine phosphatases. RNA blot analysis showed a single transcript that was most abundant in lung but present in much lower amounts in brain and heart as well.
Gebbink et al. (1991) mapped the human PTPRM gene to chromosome 18pter-q11 by Southern analysis of human/rodent somatic cell hybrid clones.
By fluorescence in situ hybridization, Suijkerbuijk et al. (1993) assigned the PTPRM gene to 18p11.2.
Crystal Structure
Human RPTP-mu is a type IIB receptor protein tyrosine phosphatase that both forms an adhesive contact itself and is involved in regulating adhesion by dephosphorylating components of cadherin-catenin complexes. Aricescu et al. (2007) described a 3.1-angstrom crystal structure of the RPTP-mu ectodomain that forms a homophilic trans (antiparallel) dimer with an extended and rigid architecture, matching the dimensions of adherens junctions. Cell surface expression of deletion constructs induces intercellular spacings that correlate with the ectodomain length. Aricescu et al. (2007) concluded that the RPTP-mu ectodomain acts as a distance gauge and plays a key regulatory function, locking the phosphatase to its appropriate functional location.
Aricescu, A. R., Siebold, C., Choudhuri, K., Chang, V. T., Lu, W., Davis, S. J., van der Merwe, P. A., Jones, E. Y. Structure of a tyrosine phosphatase adhesive interaction reveals a spacer-clamp mechanism. Science 317: 1217-1220, 2007. [PubMed: 17761881] [Full Text: https://doi.org/10.1126/science.1144646]
Gebbink, M. F. B. G., van Etten, I., Hateboer, G., Suijkerbuijk, R., Beijersbergen, R. L., Geurts van Kessel, A., Moolenaar, W. H. Cloning, expression and chromosomal localization of a new putative receptor-like protein tyrosine phosphatase. FEBS Lett. 290: 123-130, 1991. [PubMed: 1655529] [Full Text: https://doi.org/10.1016/0014-5793(91)81241-y]
Suijkerbuijk, R. F., Gebbink, M. F. G. B., Moolenaar, W. H., Geurts van Kessel, A. Fine mapping of the human receptor-like protein tyrosine phosphatase gene (PTPRM) to 18p11.2 by fluorescence in situ hybridization. Cytogenet. Cell Genet. 64: 245-246, 1993. [PubMed: 8404049] [Full Text: https://doi.org/10.1159/000133598]