Differential targeting of VDAC3 mRNA isoforms influences mitochondria morphology

作者：Michaud Morgane; Ubrig Elodie; Filleur Sophie; Erhardt Mathieu; Ephritikhine Genevieve; Marechal Drouard Laurence; Duchene Anne Marie^*

来源：Proceedings of the National Academy of Sciences, 2014, 111(24): 8991-8996.

DOI：10.1073/pnas.1402588111

• mRNA localization
• mRNA sorting
• green RNA
• porin
• plant

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 iso-forms 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.

• 出版日期2014-6-17