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Synaptic tetraspan vesicle membrane proteins are conserved but not needed for synaptogenesis and neuronal function in Caenorhabditis elegans.

ABSTRACT: Tetraspan vesicle membrane proteins (TVPs) comprise a major portion of synaptic vesicle proteins, yet their contribution to the synaptic vesicle cycle is poorly understood. TVPs are grouped in three mammalian gene families: physins, gyrins, and secretory carrier-associated membrane proteins (SCAMPs). In Caenorhabditis elegans, only a single member of each of these families exists. These three nematode TVPs colocalize to the same vesicular compartment when expressed in mammalian cells, suggesting that they could serve overlapping functions. To examine their function, C. elegans null mutants were isolated for each gene, and a triple mutant was generated. Surprisingly, these animals develop normally and exhibit normal neuronal architecture and synaptic contacts. In addition, functions of the motor and sensory systems are normal as determined by pharmacological, chemotaxis, and thermotaxis assays. Finally, direct electrophysiological analysis of the neuromuscular junction revealed no phenotype in the TVP mutants. We therefore conclude that TVPs are not needed for the basic neuronal machinery and instead may contribute to subtle higher order functions.

SUBMITTER: Abraham C

PROVIDER: S-EPMC1570102 | biostudies-literature | 2006 May

REPOSITORIES: biostudies-literature

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Synaptic tetraspan vesicle membrane proteins are conserved but not needed for synaptogenesis and neuronal function in Caenorhabditis elegans.

Abraham Christian C Hutter Harald H Palfreyman Mark T MT Spatkowski Gabriele G Weimer Robby M RM Windoffer Reinhard R Jorgensen Erik M EM Leube Rudolf E RE

Proceedings of the National Academy of Sciences of the United States of America 20060512 21

Tetraspan vesicle membrane proteins (TVPs) comprise a major portion of synaptic vesicle proteins, yet their contribution to the synaptic vesicle cycle is poorly understood. TVPs are grouped in three mammalian gene families: physins, gyrins, and secretory carrier-associated membrane proteins (SCAMPs). In Caenorhabditis elegans, only a single member of each of these families exists. These three nematode TVPs colocalize to the same vesicular compartment when expressed in mammalian cells, suggesting ...[more]

PMID: 16698939

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Dataset Information

Synaptic tetraspan vesicle membrane proteins are conserved but not needed for synaptogenesis and neuronal function in Caenorhabditis elegans.

Publications

Synaptic tetraspan vesicle membrane proteins are conserved but not needed for synaptogenesis and neuronal function in Caenorhabditis elegans.

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