1990 Fiscal Year Final Research Report Summary
Transcriptional Regulation of Eukaryotic Ribosomal Protein Genes and Function of the Proteins.
| Project/Area Number |
01470150
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
代謝生物化学
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| Research Institution | Yamanashi Medical College |
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Principal Investigator |
TSURUGI Kunio Yamanashi Medical College, Department of Biochemistry, Professor, 医学部, 教授 (10018690)
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| Co-Investigator(Kenkyū-buntansha) |
MOTIZUKI Mitsuyoshi Yamanashi Medical College, Department of Biochemistry, Research Assistant, 医学部, 助手 (90174341)
MITSUI Kazuhiro Yamanashi Medical College, Department of Biochemistry, Research Assistant, 医学部, 助手 (20174063)
ENDO Yaeta Yamanashi Medical College, Department of Biochemistry, Assistant Professor, 医学部, 助教授 (40093843)
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| Project Period (FY) |
1989 – 1990
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| Keywords | Eukaryote / Ribosome / ribosomal proteins / gene expression / Regulation / Funtion / alpha-sarcin |
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| Research Abstract |
1. The acidic ribosomal protein family of yeast S. cerevisiae consists of four 13-kDa and one 38-kDa proteins sharing a homologous carboxyl terminal sequence. The characteristics of their genes as a multigene family were investigated ; 1) All the genes except one (A2) were located on the same choromosome. 2) The genes for P2-type 13-kDa were compensated after inactivation by gene disruption while the other three were essential. 3) To investigate the translational regulation their mRNA levels were determined after a nutritional shiftup and a mild heat shock. Generally, the transcription of the acidic ribosomal proteins were similarly regulated as that of basic ribosomal proteins but each acidic ribosomal protein gene appeared to be independently regulated under different growth conditions. 4) Especially, the mRNA level for 38-kDa protein AO was retained at the normal level during the heat shock differing from the others.
2. On the structure and function of the proteins ; 1) the common carbocyl-terminal sequence of 10 residues in length was shown to be involved in the interaction with elongation factors but not in the binding to ribosomes by a study using chemically-synthesized oligopeptides. 2) The aminoterminal halves of 13-kDa proteins possessed a bilateral hydrophobic zipper which is assumed to interact to form homopolymers or bind to the 38-kDa protein which has a hydrophobic zipper in the corresponding position.
3. The molecular mechanism of ribosome-inactivation toxins, alpha-sarcin and ricin, were investigates using synthesized oligoribonucleotides as substrates. It was revealed that a loop-and-stem structure containing GAGA in the center of the loop is essential for a substrate and that ribosomal proteins strongly affect the affinity and specificity for the toxin-substrate relationship.
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