This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Gogendeau, D. Articles by Koll, F. Search for Related Content PubMed PubMed Citation Articles by Gogendeau, D. Articles by Koll, F.

Nd6p, a Novel Protein with RCC1-Like Domains Involved in Exocytosis in Paramecium tetraurelia

Delphine Gogendeau,^* Anne-Marie Keller, Akira Yanagi, Jean Cohen, and France Koll

Centre de Génétique Moléculaire, CNRS, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France

Received 22 July 2005/ Accepted 16 September 2005

In Paramecium tetraurelia, the regulated secretory pathway of dense core granules called trichocysts can be altered by mutation and genetically studied. Seventeen nondischarge (ND) genes controlling exocytosis have already been identified by a genetic approach. The site of action of the studied mutations is one of the three compartments, the cytosol, trichocyst, or plasma membrane. The only ND genes cloned to date correspond to mutants affected in the cytosol or in the trichocyst compartment. In this work, we investigated a representative of the third compartment, the plasma membrane, by cloning the ND6 gene. This gene encodes a 1,925-amino-acid protein containing two domains homologous to the regulator of chromosome condensation 1 (RCC1). In parallel, 10 new alleles of the ND6 gene were isolated. Nine of the 12 available mutations mapped in the RCC1-like domains, showing their importance for the Nd6 protein (Nd6p) function. The RCC1 protein is well known for its guanine exchange factor activity towards the small GTPase Ran but also for its involvement in membrane fusion during nuclear envelope assembly. Other proteins with RCC1-like domains are also involved in intracellular membrane fusion, but none has been described yet as involved in exocytosis. The case of Nd6p is thus the first report of such a protein with a documented role in exocytosis.

Present address: Department of Biotechnology, Senshu University of Ishinomaki, Ishinomaki 986-8580, Japan.

This article has been cited by other articles:

• Duret, L., Cohen, J., Jubin, C., Dessen, P., Gout, J.-F., Mousset, S., Aury, J.-M., Jaillon, O., Noel, B., Arnaiz, O., Betermier, M., Wincker, P., Meyer, E., Sperling, L. (2008). Analysis of sequence variability in the macronuclear DNA of Paramecium tetraurelia: A somatic view of the germline. Genome Res. 18: 585-596 [Abstract] [Full Text]  
• Gogendeau, D., Klotz, C., Arnaiz, O., Malinowska, A., Dadlez, M., de Loubresse, N. G., Ruiz, F., Koll, F., Beisson, J. (2008). Functional diversification of centrins and cell morphological complexity. J. Cell Sci. 121: 65-74 [Abstract] [Full Text]