Expression of H(+),K(+)-ATPase and glycopattern analysis in the gastric glands of Rana esculenta.
A multidisciplinary study involving lectin histochemistry, IHC, immuno-lectin blotting, and immunogold was carried out to determine the distribution of sugar residues in the glycoproteins of Rana esculenta oxynticopeptic cells. We considered animals in two experimental conditions, fasting and fed. It is known that, in mammals, the tubulovesicular membranes are rich in proteins with several functions. The proton pump H(+),K(+)-ATPase, a heterodimeric complex with a catalytic alpha-subunit and a heavily glycosylated beta-subunit, responsible for acid secretion, is the most abundant. No data have been published regarding the localization and the structures of H(+),K(+)-ATPase in amphibians. In the water frog, the luminal membrane and tubulovesicular system of oxynticopeptic cells, which differ in morphology according to their functional stage, reacted with the primary gold-conjugated antibody against the H(+),K(+)-ATPase alpha-subunit. By lectin histochemistry and immunoblotting, in the oxynticopeptic cells of R. esculenta we detected the presence of N-linked glycans having fucosylated (poly)lactosamine chains, which could correspond to the oligosaccharide chains of the beta subunit. The latter are somewhat different from those described in mammals, and this is probably because of an adaptation to the different microenvironmental conditions in which the oxynticopeptic cells find themselves, in terms of their different habits and phylogeny.
Mastrodonato
Maria
M
Dipartimento di Zoologia, Laboratorio di Istologia e Anatomia Comparata, Università degli Studi di Bari, Via Orabona, 4 I-70125 Bari, Italy.
Calamita
Giuseppe
G
Rossi
Roberta
R
Scillitani
Giovanni
G
Liquori
Giuseppa Esterina
GE
Ferri
Domenico
D
D000818:Animals; D000911:Antibodies, Monoclonal; D004435:Eating; D055098:Endocrine Cells / Q000201:enzymology; D005215:Fasting; D005753:Gastric Mucosa / Q000378:metabolism* / Q000648:ultrastructure; D006023:Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D017506:H(+)-K(+)-Exchanging ATPase / Q000096:biosynthesis* / Q000276:immunology; D006651:Histocytochemistry; D016253:Microscopy, Immunoelectron; D009844:Oligosaccharides / Q000032:analysis; D010295:Parietal Cells, Gastric / Q000201:enzymology; D037121:Plant Lectins; D021122:Protein Subunits / Q000096:biosynthesis / Q000276:immunology; D011893:Rana esculenta / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D006023:Glycoproteins; D009844:Oligosaccharides; D037121:Plant Lectins; D021122:Protein Subunits; D017506:H(+)-K(+)-Exchanging ATPase