Animals ; Extracellular Space/metabolism ; Humans ; Intracellular Space/metabolism ; Models, Biological ; Receptor-Like Protein Tyrosine Phosphatases, Class 2/chemistry ; Receptor-Like Protein Tyrosine Phosphatases, Class 2/metabolism* ; Signal Transduction ; Synapses/metabolism*
Keywords
LAR ; PTPδ ; PTPσ ; alternative splicing ; heparan sulfate ; ligands ; receptor protein tyrosine phosphatase ; synapse development ; synaptic adhesion
Abstract
Leukocyte common antigen-related receptor tyrosine phosphatases (LAR-RPTPs) have emerged as key players that organize various aspects of neuronal development, including axon guidance, neurite extension, and synapse formation and function. Recent research has highlighted the roles of LAR-RPTPs at neuronal synapses in mediating distinct synaptic adhesion pathways through interactions with a host of extracellular ligands and in governing a variety of intracellular signaling cascades through binding to various scaffolds and signaling proteins. In this chapter, we review and update current research progress on the extracellular ligands of LAR-RPTPs, regulation of their extracellular interactions by alternative splicing and heparan sulfates, and their intracellular signaling machineries. In particular, we review structural insights on complexes of LAR-RPTPs with their various ligands. These studies lend support to general molecular mechanisms underlying LAR-RPTP-mediated synaptic adhesion and signaling pathways.