FUCOSYLATED GLYCOCONJUGATES OF THE HUMAN SPERMATOZOON - COMPARISON OFTHE DOMAINS OF THESE GLYCOCONJUGATES WITH THE ALPHA-FUCOSYL BINDING-SITES, AND WITH LACTOSAMINIC GLYCOCONJUGATES AND BETA-D-GALACTOSYL BINDING-SITE DOMAINS

Fucosylated glycoconjugates play an important role in fertilization as the recognition signal of the zona pellucida. In this work, using ''c ritical'' concentrations of either, FITC Lotus tetragonolobus lectin o r FITC alpha-L-fucosyl-BSA neoglycoprotein as molecular probes, popula tion densities of fucosylated glycoconjugates and of their ''complemen tary'' molecules (carrying fucosyl receptors), were found all over the sperm surface with higher population densities in post acrosomal shea th, neck and midpiece. These results were compared with previously rep orted data on the population densities of lactosaminic compounds and t heir ''complementary'' molecules, obtained on same samples of spermato zoa. Statistical data demonstrate that fucosylated glycoconjugates sha re the same domains with biantennary N-acetyllactosaminic oligosacchar ides carrying outer galactose and bisected N-acetylglucosamine residue s. These domains highly differ with those of the lactosaminic glycopro teins carrying tri and tetraantennary N-acetyllactosaminic oligosaccha rides. These studies also show that the domains of fucosylated glycoco njugates and their ''complementary'' molecules (carrying fucosyl recep tors) locate in different zones of the spermatozoon than those of the compounds carrying beta-galactosyl receptors. Besides, the results sug gest structural differences between fucosylated glycoconjugates of the acrosome, equatorial zone and post acrosomal sheath. This may be rele vant to the different biological behavior of these compounds and zones , in fertilization.