The role of the 3' untranslated region in mRNA sorting to the vicinity of mitochondria is conserved from yeast to human cells.
We recently demonstrated, using yeast DNA microarrays, that mRNAs of polysomes that coisolate with mitochondria code for a subset of mitochondrial proteins. The majority of these mRNAs encode proteins of prokaryotic origin. Herein, we show that a similar association occurs between polysomes and mitochondria in human cells. To determine whether mRNA transport machinery is conserved from yeast to human cells, we examined the subcellular localization of human OXA1 mRNA in yeast. Oxa1p is a key component in the biogenesis of mitochondrial inner membrane and is conserved from bacteria to eukaryotic organelles. The expression of human OXA1 cDNA partially restores the respiratory capacity of yeast oxa1- cells. In this study, we demonstrate that 1) OXA1 mRNAs are remarkably enriched in mitochondrion-bound polysomes purified from yeast and human cells; 2) the presence of the human OXA1 3' untranslated region (UTR) is required for the function of the human Oxa1p inside yeast mitochondria; and 3) the accurate sorting of the human OXA1 mRNA to the vicinity of yeast mitochondria is due to the recognition by yeast proteins of the human 3' UTR. Therefore, it seems that the recognition mechanism of OXA1 3' UTR is conserved throughout evolution and is necessary for Oxa1p function.
Sylvestre
J
J
Laboratoire de Génétique Moléculaire, Unité Mixte Recherche Centre National de la Recherche Scientifique 8541, Ecole Normale Supérieure, Paris, France.
Margeot
A
A
Jacq
C
C
Dujardin
G
G
Corral-Debrinski
M
M
D003576:Electron Transport Complex IV; D019143:Evolution, Molecular; D006367:HeLa Cells; D006801:Humans; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011132:Polyribosomes / Q000378:metabolism; D034443:RNA Transport / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D020506:Untranslated Regions
D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; C090858:OXA1 protein; D012333:RNA, Messenger; D020506:Untranslated Regions; D003576:Electron Transport Complex IV