Mouse Lymphomyeloid Cells Can Function with Significantly Decreased Expression Levels of Cytochrome c

---

E. S. Shilov^1*, I. V. Kislyakov¹, E. A. Gorshkova¹, R. V. Zvartsev², M. S. Drutskaya², I. A. Mufazalov², V. P. Skulachev², and S. A. Nedospasov^3*

¹Lomonosov Moscow State University, Biological Faculty, 119991 Moscow, Russia; E-mail: shilov_evgeny@inbox.ru

²Lomonosov Moscow State University, Belozersky Institute of Physico-Chemical Biology, 119991 Moscow, Russia

³Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova st., 119991 Moscow, Russia; E-mail: sergei.nedospasov@gmail.com

^* To whom correspondence should be addressed.

Received July 23, 2014

---

Cytochrome c is an indispensable electron carrier in the mitochondrial respiratory chain and also an important mediator of the internal pathway triggering apoptosis. Mice with a complete deficiency of the Cycs gene encoding the somatic cytochrome c die during the embryogenesis. Using the technology of LoxP-cre-dependent tissue-specific recombination, we obtained some mouse strains with significantly reduced expression of cytochrome c in certain cell types (“conditional genetic knockdown”). This knockdown was achieved by abrogation of the normal splicing of the Cycs locus pre-mRNA due to an additional acceptor site inside the stop-cassette neo^r. Previously, we observed embryonic lethality in homozygous mice with the same knockdown of cytochrome c in all cells of the organism. In the present work we studied two novel mouse strains with conditional knockdown of the Cycs gene in T lymphocytes and macrophages. Somewhat surprisingly, the mice of these two strains under normal conditions were not phenotypically different from the wild-type mice, either on the whole organism level or on the level of activity of individual target cells. Thus, the amount of cytochrome c in lymphomyeloid cells does not affect their development and normal functioning.

---

KEY WORDS: cytochrome c, genetic knockdown, T lymphocytes, macrophages, cre recombinase, splicing

DOI: 10.1134/S0006297914120177

---