PathwayStep6250 PathwayStep6251 PathwayStep6258 PathwayStep6256 PathwayStep6257 PathwayStep6254 PathwayStep6255 PathwayStep6252 PathwayStep6253 PathwayStep6241 PathwayStep6240 PathwayStep3452 Signal transduction by L1 Authored: Garapati, P V, 2008-07-30 10:22:58 Besides adhesive roles in cell cell interaction, L1 functions as a signal transducing receptor providing neurons with cues from their environment for axonal growth and guidance. L1 associates with beta1 integrins on the cell surface to induce a signaling pathway involving sequential activation of pp60csrc, Vav2 -GEF, Rac1, PAK1, MEK and ERK1/2. L1 stimulates cell migration and neurite outgrowth through the MAP kinases ERK1/2. CHL1 also associates with integrins and activates a MAPK signaling pathway via pp60c-src, MEK and ERK1/2. <br>L1 also binds the Sema3A receptor neuropilin1 and acts as an obligate coreceptor to mediate Sema3A induced growth cone collapse and axon repulsion. This repulsion can be converted to attraction by homophilic binding of L1 on an apposing cell in trans with L1 complexed with Neuropilin1 (NP1) in the responding neuron.<br>L1 also interacts with FGF receptor and activates PLC gamma and DAG, resulting in the production of arachidonic acid and subsequent opening of voltage-gated channels. Edited: Garapati, P V, 2008-07-30 10:22:58 Pubmed10608864 Pubmed10818153 Pubmed12721290 Pubmed15597056 Pubmed16597699 Pubmed17189949 Reactome Database ID Release 43445144 Reactome, http://www.reactome.org ReactomeREACT_22272 Reviewed: Maness, PF, 2010-02-16 PathwayStep3458 MEK2 phosphorylates ERK-2 MEK1 phosphorylates ERK-1 L1 and NCAM1 engaged in cis-interaction Phosphorylation of L1 by p90rsk Phosphorylation of L1 by ERK Phosphorylation of L1 by CK-II Interaction of PAK1 with Rac1-GTP Activation of Rac1 by VAV2 Phosphorylation of VAV2 L1 interaction with Integrins L1 binds Neuropilin-1 L1-EGFR trans-heterodimerization L1-FGFR cis-heterodimerization