Histochemical analysis of rat testicular glycoconjugates. 2. Beta-galactosyl residues in O- and N-linked glycans in seminiferous tubules.
Rat testes have been examined with a panel of lectins that bind specifically to oligosaccharide sequences having terminal or subterminal beta-galactosyl residues in O-linked glycans, or in the outer chains of complex N-linked glycans: Arachis hypogaea (peanut, AHA), Erythrina cristagalli (coral tree, ECA), Ricinus communis (castor bean, RCA120) and Abrus precatorius (jequirity bean, APA) agglutinins. Pretreatment of sections with neuraminidase, beta-galactosidase and removal of alkali-labile O-linked sequences by beta-elimination allowed the structure of these glycans to be further explored. In spermatogonia and spermatocytes there was little evidence of glycans terminating in beta-galactosyl residues, although these were present at non-reducing terminals as sialylgalactosides. The acrosome contained two subsets of O-linked glycans terminating in sialylgalactosides, while the nuclear cap showed at least two subsets of N-linked sialylgalactosyl as well as O-linked glycans. Spermatozoa exhibited minor changes in the pattern of glycosylation, although the overall pattern of beta-galactosyl expression was similar. Binding to Sertoli cells showed the presence of some unsubstituted beta-galactosyl terminals on O-linked glycans but few such N-linked residues, while terminal beta-galactosides were scanty in tubular basement membranes.
Jones
C J
CJ
Department of Pathological Sciences, University of Manchester, UK.
Morrison
C A
CA
Stoddart
R W
RW
D000818:Animals; D002240:Carbohydrate Sequence; D005690:Galactose / Q000737:chemistry / Q000378:metabolism; D006001:Glycoconjugates / Q000737:chemistry / Q000378:metabolism*; D006651:Histocytochemistry; D037102:Lectins; D008297:Male; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D012671:Seminiferous Tubules / Q000378:metabolism*; D013091:Spermatogenesis / Q000502:physiology; D013094:Spermatozoa / Q000378:metabolism; D013737:Testis / Q000378:metabolism
D006001:Glycoconjugates; D037102:Lectins; D011134:Polysaccharides; D005690:Galactose