GANGLIOSIDE GM1 ELEVATION IN DBA/2 MOUSE EMBRYOS

The composition of whole embryo gangliosides at embryonic day E-12 was compared among the C57BL/6 (B6) DBA/2 (D2), and C3H mouse strains. N-acetylneuraminic acid was the predominant sialic acid species in the E-12 embryos. N-glycolyneuraminic acid was either undetectable or present in only trace amounts. Whole embryo ganglioside sialic concentration was significantly lower in D2 embryos than in B6 or C3H embryos. GM3 and GD3 were the most abundant ganglioside species in each strain and comprised approximately 75% of the total distribution. The D2 embryos expressed an elevation of GDI a and a reduction of GQ lb relative to B6 and C3H. Also, the level of GM1 was significantly higher in the D2 embryos than in the B6 or C3H embryos. Since a reduction of ß-galactosidase activity and an elevation of GM1 concentration in brain were previously reported in postnatal DBA mice, our results suggest that the elevated GM1 in D2 embryos may result from a reduced activity of GM1 β-galactosidase. © 1990 S. Karger AG, Basel.