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Differential targeting of VDAC3 mRNA isoforms influences mitochondria morphology.

ABSTRACT: Intracellular targeting of mRNAs has recently emerged as a prevalent mechanism to control protein localization. For mitochondria, a cotranslational model of protein import is now proposed in parallel to the conventional posttranslational model, and mitochondrial targeting of mRNAs has been demonstrated in various organisms. Voltage-dependent anion channels (VDACs) are the most abundant proteins in the outer mitochondrial membrane and the major transport pathway for numerous metabolites. Four nucleus-encoded VDACs have been identified in Arabidopsis thaliana. Alternative cleavage and polyadenylation generate two VDAC3 mRNA isoforms differing by their 3' UTR. By using quantitative RT-PCR and in vivo mRNA visualization approaches, the two mRNA variants were shown differentially associated with mitochondria. The longest mRNA presents a 3' extension named alternative UTR (aUTR) that is necessary and sufficient to target VDAC3 mRNA to the mitochondrial surface. Moreover, aUTR is sufficient for the mitochondrial targeting of a reporter transcript, and can be used as a tool to target an unrelated mRNA to the mitochondrial surface. Finally, VDAC3-aUTR mRNA variant impacts mitochondria morphology and size, demonstrating the role of mRNA targeting in mitochondria biogenesis.

SUBMITTER: Michaud M

PROVIDER: S-EPMC4066512 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Differential targeting of VDAC3 mRNA isoforms influences mitochondria morphology.

Michaud Morgane M Ubrig Elodie E Filleur Sophie S Erhardt Mathieu M Ephritikhine Geneviève G Maréchal-Drouard Laurence L Duchêne Anne-Marie AM

Proceedings of the National Academy of Sciences of the United States of America 20140602 24

Intracellular targeting of mRNAs has recently emerged as a prevalent mechanism to control protein localization. For mitochondria, a cotranslational model of protein import is now proposed in parallel to the conventional posttranslational model, and mitochondrial targeting of mRNAs has been demonstrated in various organisms. Voltage-dependent anion channels (VDACs) are the most abundant proteins in the outer mitochondrial membrane and the major transport pathway for numerous metabolites. Four nuc ...[more]

PMID: 24889622

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Differential targeting of VDAC3 mRNA isoforms influences mitochondria morphology.

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Differential targeting of VDAC3 mRNA isoforms influences mitochondria morphology.

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