title: Alternative forms of Y-box binding protein 1 and YB-1 mRNA.
abstract: The multifunctional eukaryotic protein YB-1 (Y-box binding protein 1) plays a role in DNA reparation, transcription regulation, splicing, and mRNA translation, thereby participating in many crucial events in cells. Its effect is dependent mostly on its amount, and hence, on regulation of its synthesis. Published data on regulation of synthesis of YB-1 mediated by its mRNA 5' UTR, and specifically on the 5' UTR length and the presence of TOP-like motifs in this region, are contradictory. Here we report that 5' UTRs of major forms of human, rabbit, and mouse YB-1 mRNAs are about 140 nucleotides long and contain no TOP-like motifs mentioned in the literature. Also, we have found that YB-1 specifically interacts with the 5' UTR of its own mRNA within a region of about 100 nucleotides upstream from the start codon. Apart from YB-1, translation of YB-1 mRNA in a cell free system gives an additional product with an extended N-terminus and lower electrophoretic mobility. The start codon for synthesis of the additional product is AUC at position -(60-58) of the same open reading frame as that for the major product. Also, in the cell there is an alternative YB-1 mRNA with exon 1 replaced by a part of intron 1; YB-1 synthesized in vitro from this mRNA contains, instead of its N-terminal A/P domain, 10-11 amino acids encoded by intron 1.
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.affiliation: Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation.
authors.forename: Alexander N
authors.initials: AN
authors.lastname: Doronin
authors.affiliation: Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation.
authors.forename: Irina A
authors.initials: IA
authors.lastname: Eliseeva
authors.affiliation: Department of Oncology and Radiation Therapy, Moscow State University of Medicine and Dentistry, Moscow, Russian Federation.
authors.forename: Gelena P
authors.initials: GP
authors.lastname: Guens
authors.affiliation: Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russian Federation; Department of Computational Systems Biology, Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russian Federation.
authors.forename: Ivan V
authors.initials: IV
authors.lastname: Kulakovskiy
authors.affiliation: Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation.
authors.forename: Lev P
authors.initials: LP
authors.lastname: Ovchinnikov
mesh_terms: D020121:5' Untranslated Regions; D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D057809:HEK293 Cells; D006801:Humans; D061986:MCF-7 Cells; D051379:Mice; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells; D011485:Protein Binding; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D011817:Rabbits; D051840:Y-Box-Binding Protein 1 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D020121:5' Untranslated Regions; D012333:RNA, Messenger; D051840:Y-Box-Binding Protein 1