Receptor protein tyrosine phosphatase micro: measuring where to stick.
We review here recent results on the structure and function of a receptor protein tyrosine phosphatase, RPTPmicro. In addition to their intercellular catalytic domains which bear the phosphatase activity, the RPTPs are cell-surface-receptor-type molecules and in many cases have large extracellular regions. What role can these extracellular regions play in function? For RPTPmicro, the extracellular region is known to mediate homophilic adhesion. Sequence analysis indicates that it comprises six domains: an N-terminal MAM (meprin/A5/micro), one immunoglobulin-like domain and four fibronectin type III (FN) repeats. We have determined the crystal structure of the entire extracellular region for RPTPmicro in the form of a functional adhesion dimer. The physical characteristics and dimensions of the adhesion dimer suggest a mechanism by which the location of this phosphatase can be influenced by cell-cell spacings.
Aricescu
A Radu
AR
Cancer Research UK Receptor Structure Research Group, University of Oxford, Henry Wellcome Building of Genomic Medicine, Division of Structural Biology, Roosevelt Drive, Oxford OX3 7BN, UK.
Siebold
Christian
C
Jones
E Yvonne
EY
D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D004789:Enzyme Activation / Q000502:physiology; D006801:Humans; D008958:Models, Molecular; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D054623:Receptor-Like Protein Tyrosine Phosphatases, Class 2 / Q000737:chemistry / Q000502:physiology
D054623:Receptor-Like Protein Tyrosine Phosphatases, Class 2