Cell-cell contacts are fundamental to multicellular organisms and are subject to exquisite levels of control. Human RPTPmu 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. Here we describe a 3.1 angstrom crystal structure of the RPTPmu 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. These data suggest that the RPTPmu ectodomain acts as a distance gauge and plays a key regulatory function, locking the phosphatase to its appropriate functional location.
Structure of a tyrosine phosphatase adhesive interaction reveals a spacer-clamp mechanism.,Aricescu AR, Siebold C, Choudhuri K, Chang VT, Lu W, Davis SJ, van der Merwe PA, Jones EY Science. 2007 Aug 31;317(5842):1217-20. PMID:17761881
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Aricescu AR, Hon WC, Siebold C, Lu W, van der Merwe PA, Jones EY. Molecular analysis of receptor protein tyrosine phosphatase mu-mediated cell adhesion. EMBO J. 2006 Feb 22;25(4):701-12. Epub 2006 Feb 2. PMID:16456543
↑ Aricescu AR, Siebold C, Choudhuri K, Chang VT, Lu W, Davis SJ, van der Merwe PA, Jones EY. Structure of a tyrosine phosphatase adhesive interaction reveals a spacer-clamp mechanism. Science. 2007 Aug 31;317(5842):1217-20. PMID:17761881 doi:317/5842/1217