[Hormonal control of expression of the mitochondrial genome region in animal cells].

Glucocorticoid hormone effect on expression of mitochondrial genes in the rat hepatic cells was studied. RNA, isolated from the hepatic mitochondria of adrenalectomized rats, is hybridized with mitochondrial DNA with lesser efficiency than from the normal animal liver. Daily hydrocortisone injections to adrenalectomized rats returned effectiveness of mitochondrial RNA and DNA hybridization to normal. Differences in competition findings of mitochondrial RNAs for hybridization on mitochondrial RNA were revealed. The hepatic mitochondrial RNA of normal rats is better competitor in comparison with that of adrenalectomized animals. It may be caused by deficiency of the adrenalectomized rat mitochondrial RNA in the transcripts of some mitochondrial genome region. In concurrent hybridization of mitochondrial RNAs of the normal and adrenalectomized rat liver and N-specific RNA with recombinant plasmid DNAs, bearing several restrictive fragments of the rat mitochondrial DNA, distinctions in competition were detected only on a single mitochondrial DNA fragment, having coordinates of 10 to 31 units, according to genetic map of mitochondrial DNA.