Glycosphingolipid composition of murine neuroblastoma cells: O-acetylesterase gene downregulates the expression of O-acetylated GD3.
We have studied the glycosphingolipid composition in an F-11 neuroblastoma cell line originated from hybridization of a mouse neuroblastoma cell line (N18TG-2) with rat dorsal root ganglion cells. The total lipid-bound glucose of F-11 cells was estimated to be 0.28 micrograms/mg of protein and the total lipid-bound sialic acid was 0.82 micrograms/mg of protein. The major neutral glycosphingolipids were Gb4 (37% of the total neutral glycosphingolipids), Gb3 (15%), LacCer (21%), and GlcCer (15%). The major gangliosides were found to be GM3 (37% of the total gangliosides), GD3 (27%), O-acetylated GD3 (18%), and GD1a (4%), with trace amounts of GD2. The unusually high concentration of O-acetylated GD3 is consistent with its putative role as a tumor marker. Immunocytochemical localization studies of GD3 and O-acetylated GD3, examined by mouse monoclonal antibodies R24 and D1.1, respectively, revealed that the cell bodies and processes were all positively stained. To elucidate the role of O-acetylated GD3 in tumorigenesis, we transfected F-11 cells with the O-acetylesterase gene from influenza C virus. Compared with the original cell line, the transfected cells showed a dramatic increase in the level of GD3 (150% of that in the control cells) and a significant decrease of the concentration of O-acetylated GD3 (27% of control cells). In addition, the transfected F-11 cells exhibited a morphology different from the parental cells with enlarged cell bodies and elongated neurites. We conclude that alteration of ganglioside composition, particularly the expression of GD3 and O-acetylated GD3, may be associated with the morphological changes observed in this cell line.(ABSTRACT TRUNCATED AT 250 WORDS)
Ariga
T
T
Department of Biochemistry and Molecular Biophysics, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298, USA.
Blaine
G M
GM
Yoshino
H
H
Dawson
G
G
Kanda
T
T
Zeng
G C
GC
Kasama
T
T
Kushi
Y
Y
Yu
R K
RK
D000107:Acetylation; D000115:Acetylesterase / Q000235:genetics*; D000818:Animals; D002240:Carbohydrate Sequence; D005732:Gangliosides / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008969:Molecular Sequence Data; D009447:Neuroblastoma / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D018629:Spectrometry, Mass, Secondary Ion; D013552:Swine; D014162:Transfection; D014407:Tumor Cells, Cultured
D005732:Gangliosides; C026226:ganglioside, GD3; D000115:Acetylesterase