Fucosylation events during mammalian spermatogenesis.

It will be necessary to conduct further studies to establish more precisely the localization of FT on mouse male germ cells. Antibodies to FTs are not yet available, so an immunocytochemical approach is not currently feasible. Additional cell fractionation protocols can be designed to compare plasma membrane fractions with enriched fractions of Golgi apparatus and to compare directly the activities of multiple glycosyltransferase enzymes and Golgi-specific markers in these preparations. Schachter et al. and Nyquist and colleagues have already provided experimental techniques for the isolation of Golgi fractions of good purity from rodent pachytene spermatocytes and spermatids. Ample opportunity exists, then, for a detailed analysis of the number, specificity, and localization of FT enzymes during mammalian spermatogenesis. All available data imply that these enzymes will prove to be vital components in the differentiation of cells within the seminiferous epithelium.