title: Modulation of differentiation-related gene 1 expression by cell cycle blocker mimosine, revealed by proteomic analysis.
abstract: L-mimosine, a plant amino acid, can reversibly block mammalian cells at late G1 phase and has been found to affect translation of mRNAs of the cyclin-dependent kinase inhibitor p27, eIF3a (eIF3 p170), and ribonucleotide reductase M2. The effect of mimosine on the expression of these genes may be essential for the G1 phase arrest. To determine additional genes that may be early respondents to the mimosine treatment, we performed two-dimensional gel electrophoretic analysis of [35S]methionine-labeled cell lysates followed by identification of the altered protein spots by LC-tandem mass spectrometry. In this study, the synthesis of two protein spots (MIP42 and MIP17) was found to be enhanced by mimosine, whereas the formation of another protein spot (MSP17) was severely blocked following mimosine treatment. These protein spots, MIP42, MIP17, and MSP17, were identified to be differentiation-related gene 1 (Drg-1; also called RTP, cap43, rit42, Ndrg-1, and PROXY-1), deoxyhypusine-containing eIF5A intermediate, and mature hypusine-containing eIF5A, respectively. The effect of mimosine on eIF5A maturation was due to inhibition of deoxyhypusine hydroxylase, the enzyme catalyzing the final step of hypusine biosynthesis in eIF5A. The mimosine-induced expression of Drg-1 was mainly attributable to increased transcription likely by the c-Jun/AP-1 transcription factor. Because induction of Drg-1 is an early event after mimosine treatment and is observed before a notable reduction in the steady-state level of mature eIF5A, eIF5A does not appear to be involved in the modulation of Drg-1 expression.
authors.affiliation: Department of Pharmacology and Toxicology, Indiana University Cancer Center and Walther Oncology Center/Walther Cancer Institute, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
authors.forename: Zizheng
authors.initials: Z
authors.lastname: Dong
authors.forename: Randy J
authors.initials: RJ
authors.lastname: Arnold
authors.forename: Youyun
authors.initials: Y
authors.lastname: Yang
authors.forename: Myung Hee
authors.initials: MH
authors.lastname: Park
authors.forename: Petra
authors.initials: P
authors.lastname: Hrncirova
authors.forename: Yehia
authors.initials: Y
authors.lastname: Mechref
authors.forename: Milos V
authors.initials: MV
authors.lastname: Novotny
authors.forename: Jian-Ting
authors.initials: JT
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D002453:Cell Cycle / Q000187:drug effects*; D018797:Cell Cycle Proteins / Q000096:biosynthesis*; D015180:Electrophoresis, Gel, Two-Dimensional; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D013058:Mass Spectrometry; D008898:Mimosine / Q000494:pharmacology*; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors; D008969:Molecular Sequence Data; D010448:Peptide Initiation Factors / Q000378:metabolism; D040901:Proteomics; D016601:RNA-Binding Proteins / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014158:Transcription, Genetic; D015854:Up-Regulation; D000097574:Eukaryotic Translation Initiation Factor 5A; D000099259:N-myc Downstream-Regulated Gene 1 Protein
chemical_list: D018797:Cell Cycle Proteins; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases; D008898:Mimosine; D006899:Mixed Function Oxygenases; D010448:Peptide Initiation Factors; D016601:RNA-Binding Proteins; D018808:Transcription Factor AP-1; D000097574:Eukaryotic Translation Initiation Factor 5A; D000099259:N-myc Downstream-Regulated Gene 1 Protein; C047991:deoxyhypusine hydroxylase