title: YB-1 synthesis is regulated by mTOR signaling pathway.
abstract: YB-1 is a eukaryotic protein with numerous intra- and extracellular functions based on its ability to interact with RNA, DNA, and many proteins. In spite of achievements in studying its functions, regulation of YB-1 synthesis in the cell remains poorly understood. In the current study Western and Northern blotting were used to determine the amounts of YB-1 and YB-1 mRNA in rabbit organs and several cell lines. As found, in the majority of studied eukaryotic cells a considerable proportion of YB-1 mRNA was stored in free mRNPs, i.e., was poorly translated. Also, we demonstrated that YB-1 synthesis depended on conditions that determined the rate of cell division. Specific suppression of YB-1 synthesis resulted from inhibition of the mTOR signaling pathway with inhibitor PP242, but not rapamycin. Experiments on reporter constructs showed that dependence of YB-1 mRNA translation on activity of the mTOR signaling pathway was dictated by 5' untranslated regions of this mRNA, irrelatively of the TOP-like sequences at the beginning of 5' UTR.
authors.affiliation: Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation.
authors.forename: Dmitry N
authors.initials: DN
authors.lastname: Lyabin
authors.forename: Irina A
authors.initials: IA
authors.lastname: Eliseeva
authors.forename: Lev P
authors.initials: LP
authors.lastname: Ovchinnikov
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D051379:Mice; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D011132:Polyribosomes / Q000187:drug effects / Q000378:metabolism; D014176:Protein Biosynthesis / Q000187:drug effects; D011687:Purines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D012261:Ribonucleoproteins / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*; D051840:Y-Box-Binding Protein 1 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism
chemical_list: D007211:Indoles; D011687:Purines; D012333:RNA, Messenger; D012261:Ribonucleoproteins; D051840:Y-Box-Binding Protein 1; C026452:messenger ribonucleoprotein; D058570:TOR Serine-Threonine Kinases; C572919:PP242