Rare Codons
Mostrando 1-12 de 75 artigos, teses e dissertações.
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1. Análise dos genes GHRH e GL12 em pacientes com deficiência de hormônio do crescimento congênita / GHRH and GLI2 genes analysis in patients with congenital growth hormone deficiency
Introduction: Alterations in genes related to GH secretion and pituitary organogenesis have been identified in patients with congenital GH deficiency (GHD). However, in only few cases of GHD the etiology has been established. GH-releasing hormone (GHRH) is an obvious candidate to explain isolated GH deficiency (IGHD). Previous reports in the literature did n
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/02/2012
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2. Clinical, biochemical and molecular aspects of the talassemic syndromes in the population of Pernambuco State / Aspectos clinicos, bioquimicos e moleculares das sindromes talassemicas em população do estado de Pernambuco
? Thalassemia is a frequent inherited disease of the Hb molecule found in the majority of populations and distributed worldwide. The prevalence of this syndrome in Brazil has been studied for a long time, but due to limitations in the methodology of some research, data on prevalence and clinical diversity are not fully complete. Furthermore, as a consequence
Publicado em: 2007
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3. Expressão de troponina I do musculo esqueletico de galinha em E. coli / Expression of chicken skeletal muscle troponin I in E. coli
Da interação da actina com a miosina resulta a contração muscular. Esta interação é controlada pela concentração de íons cálcio, que atuam sobre um sistema regulatório associado ao filamento de actina. O sistema regulatório é composto de uma molécula de tropomiosina e um complexo protéico composto de três polipeptídeos chamado troponina. Um
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 21/06/1991
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4. Escherichia coli ribosomes translate in vivo with variable rate.
The question of whether or not 'rare' codons are translated with the same rate as 'common' codons was investigated by measuring the translation time for two genes, lacI and bla, rich in rare codons, and comparing the results with the translation times measured on fus, tsf, tuf and rpsA which have very few rare codons. The rate of synthesis of the lac repress
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5. Codon usage in regulatory genes in Escherichia coli does not reflect selection for 'rare' codons.
It has often been suggested that differential usage of codons recognized by rare tRNA species, i.e. "rare codons", represents an evolutionary strategy to modulate gene expression. In particular, regulatory genes are reported to have an extraordinarily high frequency of rare codons. From E. coli we have compiled codon usage data for highly expressed genes, mo
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6. Overexpression of an mRNA dependent on rare codons inhibits protein synthesis and cell growth.
lambda's int gene contains an unusually high frequency of the rare arginine codons AGA and AGG, as well as dual rare Arg codons at three positions. Related work has demonstrated that Int protein expression depends on the rare AGA tRNA. Strong transcription of the int mRNA with a highly efficient ribosome-binding site leads to inhibition of Int protein synthe
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7. Genome Variability and Capsid Structural Constraints of Hepatitis A Virus
The number of synonymous mutations per synonymous site (Ks), the number of nonsynonymous mutations per nonsynonymous site (Ka), and the codon usage statistic (Nc) were calculated for several hepatitis A virus (HAV) isolates. While Ks was similar to those of poliovirus (PV) and foot-and-mouth disease virus (FMDV), Ka was 1 order of magnitude lower. The Nc par
American Society for Microbiology.
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8. A small segment of the MAT alpha 1 transcript promotes mRNA decay in Saccharomyces cerevisiae: a stimulatory role for rare codons.
Differences in decay rates of eukaryotic transcripts can be determined by discrete sequence elements within mRNAs. Through the analysis of chimeric transcripts and internal deletions, we have identified a 65-nucleotide segment of the MAT alpha 1 mRNA coding region, termed the MAT alpha 1 instability element, that is sufficient to confer instability to a stab
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9. Stop codons preceded by rare arginine codons are efficient determinants of SsrA tagging in Escherichia coli
The SsrA or tmRNA quality control system intervenes when ribosomes stall on mRNAs and directs the addition of a C-terminal peptide tag that targets the modified polypeptide for degradation. Although hundreds of SsrA-tagged proteins can be detected in cells when degradation is prevented, most of these species have not been identified. Consequently, the mRNA s
The National Academy of Sciences.
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10. The effects of leader peptide sequence and length on attenuation control of the trp operon of E.coli.
We have examined the effects of changing the length and codon content of the trp leader peptide coding region on expression of the trp operon of Escherichia coli, it had previously been shown that coupling of transcription and translation in the trp leader region is essential for both basal level control and tryptophan starvation control of transcription att
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11. Decoding with the A:I wobble pair is inefficient.
tRNAs with inosine (I) in the first position read three codons ending in U, C and A. However, A-ending codons read with I are rarely used. In Escherichia coli, CGA/U/C are all read solely by tRNAICGArg. CGU and CGC are very common codons, but CGA is very rare. Three independent in vivo assays show that translation of CGA is relatively inefficient. In the fir
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12. Simple and Efficient Method for Heterologous Expression of Clostridial Proteins
Many clostridial proteins are poorly produced in Escherichia coli. It has been suggested that this phenomena is due to the fact that several types of codons common in clostridial coding sequences are rarely used in E. coli and the quantities of the corresponding tRNAs in E. coli are not sufficient to ensure efficient translation of the corresponding clostrid
American Society for Microbiology.