HOME > Project > Laboratory of Biomembrane
Laboratory Head
Kohji Kasahara
Brochure 2018_PDF (136.9KB)
Lipid rafts are dynamic assemblies of glycosphingolipids, sphingomy-elin, cholesterol, and proteins that can be stabilized into microdomains in volved in the regulation of a number of cellular processes.
We have been investigating the association of glycosphingolipids with specific proteins in the nervous system and blood platelets.
We demonstrated that anti-ganglioside GD3 antibody co-precipitates GPI-anchored neural cell adhesion molecule TAG-1, src-family kinase Lyn, its substrate Cbp, trimeric G protein Goα of cerebellar granule cells.
TAG-1 plays roles in axonal guidance, and cellular migration. GPI anchors have no direct contact with the cyto-plasm. We demonstrated that TAG-1 transduces signal viaLyn/Cbp in ganglioside GD3-rich rafts of cerebellar granule cells. Chemokine SDF-1α triggers the chemoattraction of cerebellar granule cells during cerebellar development.
We demonstrated that SDF-1α stimulates GTPγS binding to Goα, and causes Goα translocation to lipid rafts, leading to growth cone collapse of cerebellar granule cells.
Sphingomyelin-rich rafts of platelets
Fibrin associates with lipid rafts on the platelets and raft integrity is required for clot retraction. We propose that clot retraction is mediated by factor XIII-dependent fibrin-integrin αIIbβ3-myosin axis in sphingomyelin-rich membrane rafts.
Laboratory Head Kohji Kasahara