Translation elongation factor 2 depletion by siRNA in mouse liver leads to mTOR-independent translational upregulation of ribosomal protein genes.

Autor: Gerashchenko MV; Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA. mgerashchenko@bwh.harvard.edu., Nesterchuk MV; Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region, Russia., Smekalova EM; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA., Paulo JA; Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA., Kowalski PS; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA., Akulich KA; Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119992, Russia., Bogorad R; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA., Dmitriev SE; Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, 119992, Russia., Gygi S; Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA., Zatsepin T; Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region, Russia.; Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia., Anderson DG; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02142, USA., Gladyshev VN; Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA., Koteliansky VE; Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region, Russia. kotelianskiv@gmail.com.
Jazyk: angličtina
Zdroj: Scientific reports [Sci Rep] 2020 Sep 23; Vol. 10 (1), pp. 15473. Date of Electronic Publication: 2020 Sep 23.
DOI: 10.1038/s41598-020-72399-4
Abstrakt: Due to breakthroughs in RNAi and genome editing methods in the past decade, it is now easier than ever to study fine details of protein synthesis in animal models. However, most of our understanding of translation comes from unicellular organisms and cultured mammalian cells. In this study, we demonstrate the feasibility of perturbing protein synthesis in a mouse liver by targeting translation elongation factor 2 (eEF2) with RNAi. We were able to achieve over 90% knockdown efficacy and maintain it for 2 weeks effectively slowing down the rate of translation elongation. As the total protein yield declined, both proteomics and ribosome profiling assays showed robust translational upregulation of ribosomal proteins relative to other proteins. Although all these genes bear the TOP regulatory motif, the branch of the mTOR pathway responsible for translation regulation was not activated. Paradoxically, coordinated translational upregulation of ribosomal proteins only occurred in the liver but not in murine cell culture. Thus, the upregulation of ribosomal transcripts likely occurred via passive mTOR-independent mechanisms. Impaired elongation sequesters ribosomes on mRNA and creates a shortage of free ribosomes. This leads to preferential translation of transcripts with high initiation rates such as ribosomal proteins. Furthermore, severe eEF2 shortage reduces the negative impact of positively charged amino acids frequent in ribosomal proteins on ribosome progression.
Databáze: MEDLINE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje