In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 100, No. 13 ( 2003-06-24), p. 7454-7459
Kurzfassung:
Glycosphingolipids form glycosphingolipid signaling microdomains. Here, we report an unrecognized type of phosphatidylglucoside (PhGlc)-based lipid microdomain in HL60 cells. Treatment of cells with rGL-7, which preferentially reacts with PhGlc, induced differentiation of HL60 cells. This was manifested by the appearance of nitroblue tetrazolium-positive cells together with CD38 expression and c-Myc down-regulation. We determined the molecular mechanisms underlying early stages of signal transduction. rGL-7 treatment induced rapid tyrosine phosphorylation of Src family protein kinases Lyn and Hck. Reduction of endogenous cholesterol after application of methyl-β-cyclodextrin suppressed rGL-7-stimulated tyrosine phosphorylation. Phosphorylated proteins and PhGlc colocalized in the Triton X-100 insoluble, light buoyant density fraction after sucrose gradient ultracentrifugation of HL60 cell lysates. This suggests PhGlc-based microdomain is involved in GL-7 signaling. Ligation of known components of microdomains, such as sphingomyelin and ganglioside GM1, with corresponding antibodies failed to induce differentiation and tyrosine phosphorylation. These results show that PhGlc constitutes a previously undescribed lipid signaling domain, and the glucose residue of PhGlc is critical for organization of the carbohydrate-dependent signaling domain involved in cellular differentiation of HL60 cells.
Materialart:
Online-Ressource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.1232503100
Sprache:
Englisch
Verlag:
Proceedings of the National Academy of Sciences
Publikationsdatum:
2003
ZDB Id:
209104-5
ZDB Id:
1461794-8
SSG:
11
SSG:
12
Permalink
