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PubMed · 8948428

Co-ordinate decrease in the expression of the mitochondrial genome and nuclear genes for mitochondrial proteins in the lactation-induced mitochondrial hypotrophy of rat brown fat.

I Martin·M Giralt·O Viñas·R Iglesias·T Mampel·F Villarroya
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Abstract

The relative abundance of the mitochondrial-encoded mRNAs for cytochrome c oxidase subunit II and NADH dehydrogenase subunit I was lower in brown adipose tissue (BAT) from lactating rats than in virgin controls. This decrease was in parallel with a significant decrease in mitochondrial 16 S rRNA levels and in the relative content of mitochondrial DNA in the tissue. BAT from lactating rats showed lowered mRNA expression of the nuclear-encoded genes for the mitochondrial uncoupling protein, subunit IV of cytochrome c oxidase and the adenine nucleotide translocase isoforms ANT1 and ANT2, whereas mRNA levels for the ATP synthase beta-subunit were unchanged. However, the relative content of this last protein was lower in BAT mitochondria from lactating rats than in virgin controls. It is concluded that lactation-induced mitochondrial hypotrophy in BAT is associated with a co-ordinate decrease in the expression of the mitochondrial genome and nuclear genes for mitochondrial proteins. This decrease is caused by regulatory events acting at different levels, including pre- and post-transcriptional regulation. BAT appears to be a useful model with which to investigate the molecular mechanisms involved in the co-ordination of the expression of the mitochondrial and nuclear genomes during mitochondrial biogenesis.

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Adipose Tissue, BrownAnimalsBlotting, NorthernBlotting, SouthernBlotting, WesternCell NucleusDNA, MitochondrialElectron Transport Complex IVFemaleGene Expression RegulationHumansLactationMitochondriaMitochondrial ADP, ATP TranslocasesRNARNA, MessengerRNA, MitochondrialRatsRats, WistarJournal ArticleResearch Support, Non-U.S. Gov't

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I Martin, M Giralt, O Viñas, R Iglesias, T Mampel, F Villarroya. 1995-06-15. Co-ordinate decrease in the expression of the mitochondrial genome and nuclear genes for mitochondrial proteins in the lactation-induced mitochondrial hypotrophy of rat brown fat.. https://doi.org/10.1042/bj3080749

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