HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE ADVANCED SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Tanaka, D. Articles by Doi, M. Search for Related Content PubMed Articles by Tanaka, D. Articles by Doi, M.

Neuroscience Research Institute, AIST, Tsukuba, Ibaraki 305-8566, Japan

Rab proteins play a critical role in intracellular vesicle trafficking and require post-translational modification by adding lipids at the C-terminus for proper functions. This modification is preceded by the formation of a trimeric protein complex with the Rab escort protein (REP) and the Rab geranylgeranyltransferase (RabGGTase). However, the genetic hierarchy among these proteins and the tissue-specificity of each protein function are not yet clearly understood. Here we identified the Caenorhabditis elegans rep-1 gene and found that a rep-1 mutant showed a mild defect in synaptic transmission and defecation behaviors. Genetic analyses using the exocytic Rab mutants rab-3 or rab-27 suggested that rep-1 functions only in the RAB-27 pathway, and not in the RAB-3 pathway, for synaptic transmission at neuromuscular junctions. However, the disruption of REP-1 did not cause defecation defects compared to severe defects in either RAB-27 or RabGGTase disruption, suggesting that REP-1 is not essential for RAB-27 signaling in defection. Some Rab proteins did not physically interact with REP-1, and localization of these Rab proteins was not severely affected by REP-1 disruption. These findings suggest that REP-1 functions are required in specific Rab pathways and in specific tissues, and that some Rab proteins are functionally prenylated without REP-1.

^aPresent address: Evaluation and Licensing Division, Pharmaceutical and Food Safety Bureau, Ministry of Health, Labor and Welfare, Tokyo 100-8916, Japan.

^* Correspondence: doi-m{at}aist.go.jp