Mastrodonato Maria, Calamita Giuseppe, Rossi Roberta, Scillitani Giovanni, Liquori Giuseppa Esterina, Ferri Domenico
Dipartimento di Zoologia, Laboratorio di Istologia e Anatomia Comparata, Università degli Studi di Bari, Via Orabona, 4 I-70125 Bari, Italy.
J Histochem Cytochem. 2009 Mar;57(3):215-25. doi: 10.1369/jhc.2008.952234. Epub 2008 Nov 11.
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.
开展了一项多学科研究，涉及凝集素组织化学、免疫组织化学、免疫凝集素印迹法和免疫金法，以确定食用蛙壁细胞糖蛋白中糖残基的分布。我们研究了处于禁食和进食两种实验条件下的动物。已知在哺乳动物中，微管泡膜富含具有多种功能的蛋白质。质子泵H(+)，K(+)-ATP酶是最丰富的一种蛋白质，它是一种异源二聚体复合物，由催化性α亚基和高度糖基化的β亚基组成，负责酸分泌。关于两栖动物中H(+)，K(+)-ATP酶的定位和结构，尚未有数据发表。在食用蛙中，壁细胞的腔面膜和微管泡系统根据其功能阶段在形态上有所不同，它们与抗H(+)，K(+)-ATP酶α亚基的一级金标抗体发生反应。通过凝集素组织化学和免疫印迹法，在食用蛙的壁细胞中，我们检测到存在具有岩藻糖基化（多）乳糖胺链的N-连接聚糖，这可能与β亚基的寡糖链相对应。后者与哺乳动物中描述的有所不同，这可能是由于壁细胞所处的不同微环境条件，在习性和系统发育方面存在差异而导致的适应性变化。
