Changes in the ultrastructure and glycoproteins of the cyst wall of Colpoda cucullus during resting encystment
Our previous studies on long-term resting encystment of Colpoda inflata showed transcriptional activity of the macronucleus and the occurrence of protein synthesis. In this work we have investigated the structure, the glycoprotein composition, and the lectin-binding site localization of the cyst wall of C. cucullus at increasing cyst ages, by means of scanning and transmission electron microscopy, confocal microscopy, and cytochemical and lectin blotting techniques. During an 18-day resting encystment, the cyst wall undergoes structural modifications resulting in the compaction of its previously-formed layers and the production of new material that is placed on the inner side of the cyst wall. Changes in the localization of ConA-/WGA-binding sites have been checked by comparing 7-day-old cysts to 1-day-old ones. Moreover, differences in the electrophoretic and ConA-/WGA-positive patterns have been found in 18-day-old cysts when compared to 1-day-old ones. The results of in vivo ConA and WGA assays suggest that ConA promotes encystment and delays excystment.
Document Type: Original Article
Affiliations: 1: Department for the Study of the Territory and its Resources, University of Genoa, Corso Europa 26, I-16132 Genoa, Italy; E-mail: [email protected] 2: Department of Ethology, Ecology and Evolution, University of Pisa, Via Volta 4, I-56126 Pisa, Italy 3: Department of Pharmacology & Physiology, Drexel University College of Medicine, NCB 245 N, 15th Street, PA 19102 Philadelphia, USA 4: Department of Experimental, Environmental and Applied Biology, University of Genoa, Viale Benedetto XV 5, I-16132 Genova, Italy
Publication date: 2002-12-01