ALPHA-GALACTOSIDASE TRANSGENIC MOUSE - HETEROGENEOUS GENE-EXPRESSION AND POSTTRANSLATIONAL GLYCOSYLATION IN TISSUES

We produced six transgenic mouse lines expressing human alpha-galactos idase (alpha-Gal) in order to evaluate its posttranslational modificat ion. Among them, serum alpha-Gal activity increased 3000-fold in two t ransgenic mouse lines (TgN2 and TgN51), as compared to that in non-tra nsgenic lines. The heart and liver of the TgN2 mouse expressed a high amount of transcript as well as high alpha-Gal activity. Its gene prod ucts in the heart and kidney were sensitive to endoglycosidase H diges tion, but those in the spleen and liver were largely resistant. Glycop eptidase F treatment confirmed an identical molecular mass for the pep tide moiety of the enzyme. We concluded that heterogeneous molecular m ass of the gene products was caused by different degrees of posttransl ational glycosylation in murine tissues.