Cheng L J, Hufnagel L A
Department of Microbiology, University of Rhode Island, Kingston 02881.
Dev Genet. 1992;13(1):26-33. doi: 10.1002/dvg.1020130105.
To investigate the role of cilia in mating interactions of Tetrahymena thermophila, ciliary membrane-rich fractions were isolated from two wild-type strains, a non-discharge mucocyst mutant which possesses mating behavior similar to wild-type, and a mating mutant which is able to costimulate cells of complementary mating type but cannot enter into pair formation. In each case, proteins from the ciliary membrane-rich fractions of starved, mating-competent ("initiated") cells were compared with those from non-starved, mating-incompetent ("non-initiated") cells, by gel electrophoresis and lectin blotting. In stained gels, a 43 kDa polypeptide was reduced or absent in initiated cells but present in non-initiated cells, in all strains. In silver-stained gels, a 25 kDa polypeptide was present in all strains, both initiated and non-initiated. In blots probed with Con A-peroxidase, a 25 kDa glycoprotein was present in ciliary membrane fractions from non-initiated cells and absent in membranes of initiated cells of the two wild-type strains and the mucocyst mutant, but is present in initiated and non-initiated cells of the mating mutant (several hypotheses are presented to explain these findings). In addition, ciliary proteins of the mating mutant included at least two unique Con A-binding polypeptides. Our results support the idea that development of mating competence during starvation involves an extensive remodeling of ciliary membranes, and identify a 25 kDa glycoconjugate as having a potential role in control of pair formation during mating.
为了研究纤毛在嗜热四膜虫交配相互作用中的作用，从两个野生型菌株、一个具有与野生型相似交配行为的非分泌性粘液囊突变体以及一个能够共刺激互补交配型细胞但不能形成配对的交配突变体中分离出富含纤毛膜的组分。在每种情况下，通过凝胶电泳和凝集素印迹法，将饥饿的、具有交配能力（“启动”）的细胞的富含纤毛膜组分中的蛋白质与未饥饿的、无交配能力（“未启动”）的细胞中的蛋白质进行比较。在染色凝胶中，所有菌株中，一种43 kDa的多肽在启动细胞中减少或缺失，但在未启动细胞中存在。在银染凝胶中，一种25 kDa的多肽在所有菌株的启动和未启动细胞中均存在。在用伴刀豆球蛋白A-过氧化物酶探测的印迹中，一种25 kDa的糖蛋白存在于未启动细胞的纤毛膜组分中，在两个野生型菌株和粘液囊突变体的启动细胞的膜中不存在，但在交配突变体的启动和未启动细胞中存在（提出了几种假说来解释这些发现）。此外，交配突变体的纤毛蛋白包括至少两种独特的伴刀豆球蛋白A结合多肽。我们的结果支持这样一种观点，即饥饿期间交配能力的发展涉及纤毛膜的广泛重塑，并确定一种25 kDa的糖缀合物在交配期间配对形成的控制中具有潜在作用。
