Significance of glycosphingolipid fatty acid chain length on membrane microdomain-mediated signal transduction.
Lactosylceramide (LacCer), a neutral glycosphingolipid, is abundantly expressed on human neutrophils, and specifically recognizes several pathogenic microorganisms. LacCer forms membrane microdomains coupled with the Src family kinase Lyn on the plasma membrane, and ligand binding to LacCer activates Lyn, resulting in neutrophil functions. In contrast, neutrophilic differentiated HL-60 cells do not have Lyn-associated LacCer-enriched microdomains and lack LacCer-mediated functions. In neutrophil plasma membranes, the very long fatty acid C24:0 and C24:1 chains are the main components of LacCer, whereas plasma membrane of D-HL-60 cells mainly includes C16-LacCer species. Here, we suggest that LacCer species containing very long fatty acid chains are indispensable for the association of Lyn with LacCer-enriched microdomains and LacCer-mediated functions.
Iwabuchi
Kazuhisa
K
Institute for Environmental and Gender-specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba 279-0023, Japan. iwabuchi@juntendo.ac.jp
Nakayama
Hitoshi
H
Iwahara
Chihiro
C
Takamori
Kenji
K
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism / Q000502:physiology; D005227:Fatty Acids / Q000378:metabolism* / Q000502:physiology; D006028:Glycosphingolipids / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007790:Lactosylceramides / Q000378:metabolism / Q000502:physiology; D021962:Membrane Microdomains / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology*; D008954:Models, Biological; D015398:Signal Transduction / Q000502:physiology*; D019061:src-Family Kinases / Q000378:metabolism / Q000502:physiology
D015703:Antigens, CD; D005227:Fatty Acids; D006028:Glycosphingolipids; D007790:Lactosylceramides; C009744:CDw17 antigen; C060902:lyn protein-tyrosine kinase; D019061:src-Family Kinases