title: Amino acid limitation induces expression of ATF5 mRNA at the post-transcriptional level.
abstract: ATF5 is a transcription factor in the cAMP response element (CRE)-binding protein/activating transcription factor (CREB/ATF) family. We studied the effect of amino acid limitation on ATF5 mRNA levels in a mammalian cell line. Northern-blot analysis demonstrated that limitation of a single amino acid, glutamine, methionine, or leucine, resulted in increased ATF5 mRNA levels in HeLaS3 cells. This resulted, at least in part, from increased half-life of the ATF5 mRNA transcript. Cycloheximide inhibited the increase in ATF5 mRNA expression induced by glutamine limitation, indicating that it was dependent on de novo protein synthesis. Moreover, rapamycin had no effect on basal ATF5 mRNA expression or on increased expression induced by glutamine limitation. These results indicate that amino acid limitation regulates ATF5 mRNA expression during post-transcription in a rapamycin-independent manner. The potential role for ATF5 in protecting cells from amino acid-limitation is of considerable interest.
authors.affiliation: Laboratory of Environmental Molecular Physiology, School of Life Science, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Watatani
authors.forename: Natsumi
authors.initials: N
authors.lastname: Kimura
authors.forename: Yusuke I
authors.initials: YI
authors.lastname: Shimizu
authors.forename: Itsuka
authors.initials: I
authors.lastname: Akiyama
authors.forename: Daijuro
authors.initials: D
authors.lastname: Tonaki
authors.forename: Hidenori
authors.initials: H
authors.lastname: Hirose
authors.forename: Shigeru
authors.initials: S
authors.lastname: Takahashi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takahashi
mesh_terms: D051696:Activating Transcription Factors / Q000096:biosynthesis*; D000596:Amino Acids / Q000172:deficiency*; D015152:Blotting, Northern; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D003513:Cycloheximide / Q000494:pharmacology; D018076:DNA, Complementary; D003609:Dactinomycin / Q000494:pharmacology; D006801:Humans; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011494:Protein Kinases / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000378:metabolism*; D020123:Sirolimus / Q000494:pharmacology; D058570:TOR Serine-Threonine Kinases
chemical_list: C507532:ATF5 protein, human; D051696:Activating Transcription Factors; D000596:Amino Acids; D018076:DNA, Complementary; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D003609:Dactinomycin; D003513:Cycloheximide; D011494:Protein Kinases; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases; D020123:Sirolimus