Abstract:
:Mammalian mitochondrial ribosomes contain two prokaryotic-like rRNAs, 12S and 16S, both encoded by mitochondrial DNA. As opposed to cytosolic ribosomes, however, these ribosomes are not thought to contain 5S rRNA. For this reason, it has been unclear whether 5S rRNA, which can be detected in mitochondrial preparations, is an authentic organellar species imported from the cytosol or is merely a copurifying cytosol-derived contaminant. We now show that 5S rRNA is tightly associated with highly purified mitochondrial fractions of human and rat cells and that 5S rRNA transcripts derived from a synthetic gene transfected transiently into human cells are both expressed in vivo and present in highly purified mitochondria and mitoplasts. We conclude that 5S rRNA is imported into mammalian mitochondria, but its function there still remains to be clarified.
journal_name
Mol Biol Celljournal_title
Molecular biology of the cellauthors
Magalhães PJ,Andreu AL,Schon EAdoi
10.1091/mbc.9.9.2375subject
Has Abstractpub_date
1998-09-01 00:00:00pages
2375-82issue
9eissn
1059-1524issn
1939-4586journal_volume
9pub_type
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