• Title/Summary/Keyword: Ribosomal protein

Search Result 248, Processing Time 0.029 seconds

Study on the Specificity Alteration of Mammalian UV Endonuclease III

  • Lee, Jae-Yung;Kim, Joon
    • BMB Reports
    • /
    • v.30 no.1
    • /
    • pp.66-72
    • /
    • 1997
  • A mammalian DNA repair enzyme, UV endonuclease III which also functions as a ribosomal protein S3 (rpS3), was purified from mouse cells and characterized. UV endonuclease III was previously cloned and known to yield a peptide of 32 kDa upon expression in E. coli [Kim et al., (1995) J. Bioi. Chem. 270, 13620-13629]. However, biochemically purified UV endonuclease III, which has a sedimentation coefficient of 3.25, appears to have an additional peptide of 28 kDa. It appears that two bands were derived from one complex, judging from the comparison of the nuclease activity on the native and SDS-gel electrophoreses. UV endonuclease III becomes non-specific upon purification and this phenomenon is more significant in the case of pure fractions of the enzyme. Non-specific activity was not influenced by pH or any salt conditions.

  • PDF

Ribosomal Crystallography: Peptide Bond Formation, Chaperone Assistance and Antibiotics Activity

  • Yonath, Ada
    • Molecules and Cells
    • /
    • v.20 no.1
    • /
    • pp.1-16
    • /
    • 2005
  • The peptidyl transferase center (PTC) is located in a protein free environment, thus confirming that the ribosome is a ribozyme. This arched void has dimensions suitable for accommodating the 3'ends of the A-and the P-site tRNAs, and is situated within a universal sizable symmetry-related region that connects all ribosomal functional centers involved in amino-acid polymerization. The linkage between the elaborate PTC architecture and the A-site tRNA position revealed that the A-to P-site passage of the tRNA 3'end is performed by a rotatory motion, which leads to stereochemistry suitable for peptide bond formation and for substrate mediated catalysis, thus suggesting that the PTC evolved by genefusion. Adjacent to the PTC is the entrance of the protein exit tunnel, shown to play active roles in sequence-specific gating of nascent chains and in responding to cellular signals. This tunnel also provides a site that may be exploited for local co-translational folding and seems to assist in nascent chain trafficking into the hydrophobic space formed by the first bacterial chaperone, the trigger factor. Many antibiotics target ribosomes. Although the ribosome is highly conserved, subtle sequence and/or conformational variations enable drug selectivity, thus facilitating clinical usage. Comparisons of high-resolution structures of complexes of antibiotics bound to ribosomes from eubacteria resembling pathogens, to an archaeon that shares properties with eukaryotes and to its mutant that allows antibiotics binding, demonstrated the unambiguous difference between mere binding and therapeutical effectiveness. The observed variability in antibiotics inhibitory modes, accompanied by the elucidation of the structural basis to antibiotics mechanism justifies expectations for structural based improved properties of existing compounds as well as for the development of novel drugs.

Association of Three Polymorphisms in Porcine Ribosomal protein L27a (RPL27A) Gene with Meat-quality Traits

  • Cho, Eun-Seok;Jeon, Hyeon-Jeong;Lee, Si-Woo;Raveendar, Sebastian;Jang, Gul-Won;Kim, Tae-Hun;Lee, Kyung-Tai
    • Journal of Animal Science and Technology
    • /
    • v.55 no.6
    • /
    • pp.509-513
    • /
    • 2013
  • We identified molecular markers associated with meat-quality traits in the porcine RPL27A (ribosomal protein L27a) gene. Three single nucleotide polymorphisms (SNPs) were discovered in the porcine RPL27A gene: g.920T>C, g.1013T>C, and g.1046T>C. The g.920 T>C SNP was significantly associated with pH24 (P < 0.05) and collagen (P < 0.05), while the g.1013T>C and g.1046T>C SNPs were significantly associated with moisture (P < 0.05). Either the TTT or CCC haplotype was significantly associated with moisture, pH24 and collagen (P < 0.05, respectively). The genotypes of RPL27A associated with meat-quality traits were all located in intron 2. The three SNPs of the RPL27A found in this study will provide useful information for genetic characterization or association studies of meat-quality traits in other populations. Additionally, these markers could potentially be applied in pig breeding programs to improve meat-quality traits after validation in other populations.

Double-stranded RNA virus in Korean Isolate IH-2 of Trichomonas vaginalis

  • Kim, Jong-Wook;Chung, Pyung-Rim;Hwang, Myung-Ki;Choi, Eun-Young
    • Parasites, Hosts and Diseases
    • /
    • v.45 no.2 s.142
    • /
    • pp.87-94
    • /
    • 2007
  • In this study, we describe Korean isolates of Trichomonas vaginalis infected with double-stranded (ds) RNA virus (TVV). One T. vaginalis isolate infected with TVV IH-2 evidenced weak pathogenicity in the mouse assay coupled with the persistent presence of a dsRNA, thereby indicating a hypovirulence effect of dsRNA in T. vaginalis. Cloning and sequence analysis results revealed that the genomic dsRNA of TVV IH-2 was 4,647 bp in length and evidenced a sequence identity of 80% with the previously-described TVV 1-1 and 1-5, but only a 42% identity with TVV 2-1 and 3 isolates. It harbored 2 overlapping open reading frames of the putative capsid protein and dsRNA-dependent RNA polymerase (RdRp). As previously observed in the TVV isolates 1-1 and 1-5, a conserved ribosomal slip-page heptamer (CCUUUUU) and its surrounding sequence context within the consensus 14-nt overlap implied the gene expression of a capsid protein-RdRp fusion protein, occurring as the result of a potential ribosomal frameshift event. The phylogenetic analysis of RdRp showed that the Korean TVV If-2 isolate formed a compact group with TVV 1-1 and 1-5 isolates, which was divergent from TVV 2-1, 3 and other viral isolates classified as members of the Giardiavirus genus.

JNK activation induced by ribotoxic stress is initiated from 80S monosomes but not polysomes

  • Kim, Tae-Sung;Kim, Hag Dong;Park, Yong Jun;Kong, EunBin;Yang, Hee Woong;Jung, Youjin;Kim, YongJoong;Kim, Joon
    • BMB Reports
    • /
    • v.52 no.8
    • /
    • pp.502-507
    • /
    • 2019
  • Translation is a costly, but inevitable, cell maintenance process. To reduce unnecessary ATP consumption in cells, a fine-tuning mechanism is needed for both ribosome biogenesis and translation. Previous studies have suggested that the ribosome functions as a hub for many cellular signals such as ribotoxic stress response, mammalian target of rapamycin (mTOR), and ribosomal S6 kinase (RSK) signaling. Therefore, we investigated the relationship between ribosomes and mitogen-activated protein kinase (MAPK) activation under ribotoxic stress conditions and found that the activation of c-Jun N-terminal kinases (JNKs) was suppressed by ribosomal protein knockdown but that of p38 was not. In addition, we found that JNK activation is driven by the association of inactive JNK in the 80S monosomes rather than the polysomes. Overall, these data suggest that the activation of JNKs by ribotoxic stress is attributable to 80S monosomes. These 80S monosomes are active ribosomes that are ready to initiate protein translation, rather than polysomes that are already acting ribosomes involved in translation elongation.

Centromere protein U enhances the progression of bladder cancer by promoting mitochondrial ribosomal protein s28 expression

  • Liu, Bei-Bei;Ma, Tao;Sun, Wei;Gao, Wu-Yue;Liu, Jian-Min;Li, Li-Qiang;Li, Wen-Yong;Wang, Sheng;Guo, Yuan-Yuan
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.25 no.2
    • /
    • pp.119-129
    • /
    • 2021
  • Bladder cancer is one of the most common types of cancer. Most gene mutations related to bladder cancer are dominantly acquired gene mutations and are not inherited. Previous comparative transcriptome analysis of urinary bladder cancer and control samples has revealed a set of genes that may play a role in tumor progression. Here we set out to investigate further the expression of two candidate genes, centromere protein U (CENPU) and mitochondrial ribosomal protein s28 (MRPS28) to better understand their role in bladder cancer pathogenesis. Our results confirmed that CENPU is up-regulated in human bladder cancer tissues at mRNA and protein levels. Gain-of-function and loss-of-function studies in T24 human urinary bladder cancer cell line revealed a hierarchical relationship between CENPU and MRPS28 in the regulation of cell viability, migration and invasion activity. CENPU expression was also up-regulated in in vivo nude mice xenograft model of bladder cancer and mice overexpressing CENPU had significantly higher tumor volume. In summary, our findings identify CENPU and MRPS28 in the molecular pathogenesis of bladder cancer and suggest that CENPU enhances the progression of bladder cancer by promoting MRPS28 expression.