Disease relevance of tetR

• Interaction between E. coli RNA polymerase and the tetR promoter from pSC101: homologies and differences with other E. coli promoter systems from close contact point studies [1].
• A fusion protein containing the tet repressor (tetR) and the activating domain of the herpes simplex virus protein VP16, which converts the repressor into a transcription activator, was produced in beta cells of transgenic mice under control of the insulin promoter [2].
• Other routes via water and food plants (vegetables) have been investigated less, although resistance genes transfer in aquatic environments as evidenced from sequence comparison of such genes (e.g. tetR, floR in Salmonella typhimurium DT104) [3].
• Screens were designed based upon fusions with three antibiotic induced promoters: the tetracycline induced tetA/tetR promoter from transposon Tn10, the erythromycin induced promoter from the Staphylococcus aureus ermC erythromycin-resistance gene and the chloramphenicol induced promoter from the S. aureus cat86 chloramphenicol-resistance gene [4].
• Tetracycline repressor-regulated gene repression in recombinant human cytomegalovirus [5].

High impact information on tetR

• Transgenic trypanosomes expressing the tetracycline repressor of Escherichia coli exhibited inducer (tetracycline)-dependent expression of chromosomally integrated reporter genes under the control of a procyclic acidic repetitive protein (PARP) promoter bearing a tet operator [6].
• Conditional ectopic expression of C/EBP beta was accomplished by using an artificial transcriptional regulatory system based on the Escherichia coli tetracycline repressor to generate a stable cell line, beta 2, that expresses C/EBP beta mRNA and protein in a tightly controlled tetracycline dose-dependent manner [7].
• Differential regulation of the Tn10-encoded tetracycline resistance genes tetA and tetR by the tandem tet operators O1 and O2 [8].
• The amino acid sequence of the N and C termini are in agreement with the gene start and stop determined from the nucleotide sequence of the Tn10 tetR gene [9].
• One tetracycline repressor (TetR) mutant gave rise to rtTA, a tetracycline-controlled transactivator that requires doxycycline (Dox) for binding to tet operators and thus for the activation of P(tet) promoters [10].

Chemical compound and disease context of tetR

• The interaction between E. coli RNA polymerase and the tetR promoter from pSC101, was studied by protection and premodification experiments, using dimethyl sulfate, methylation of single stranded cytosines, and DNAase I footprinting [1].
• Clinical isolates of E. coli were examined successfully for tetracycline resistance and for the presence of tetR [11].
• By transiently expressing a chimeric receptor containing Escherichia coli tetracycline repressor (TetR) and LXRbeta LBD and a reporter with a TetR binding site, we show that mutant F268A lost the ability to activate transcription of the reporter, whereas mutant T272A still has an activity similar to that of the wild-type LXRbeta [12].

Biological context of tetR

• Taken together, the DNA sequence and the genetic data indicate that tetR encodes a 207 amino acid protein with a calculated molecular weight of 23,328 [13].
• The tetR gene is located on a 701 base pair HincII restriction fragment [13].
• Absence of initiation from the tetR gene was correlated with the unusual structure present within its promoter region in form V DNA [14].
• The Escherichia coli strain designed to detect tetracyclines contains a single copy of a tetA(B)-lacZ transcriptional fusion integrated into the chromosome and the tetR gene encoding the tetracycline repressor on a plasmid [15].
• The tetracycline resistance regulatory gene (tetR) of transposon Tn10 was analyzed by a combination of methods involving gene fusion and cloning [16].

Anatomical context of tetR

• In conclusion, the tetR real-time PCR offers new methods for detection and quantification of tetracycline-resistant bacteria and tTA in transfected cell-lines or transgenic animals [11].

Associations of tetR with chemical compounds

• The Tn10 tetR gene encodes the repressor that regulates transcription of the Tn10 tetracycline resistance determinant [13].
• All of these Atr mutations are located in the Tn10 tet region; the majority (18 of 20) have no effect on tetR repressor function [17].
• An example is given in which a galK gene, lacking the normal initiator methionine codon, is fused to various segments of the 5' end of the tetR gene of pBR322 [18].

Other interactions of tetR

• Subcloning, transposon mutagenesis, and DNA sequence analysis revealed that this DNA fragment contained two divergently transcribed genes, tetA and tetR, encoding products that were very similar to proteins of the Tet(A) class of tetracycline resistance systems [19].
• In addition, it appears that E. coli cannot tolerate constitutive expression of the wild-type tetA gene from a multicopy plasmid containing a tetR deletion [17].
• Tetracycline in the medium induces divergent transcription of the tetA and tetR genes within the transposon, and this transcription extends beyond the transposon in both directions into the bacterial genes [20].
• The structural genes for tetA, the Tn10 tetracycline-resistance function, and for tetR, the Tn10 tet repressor, are transcribed in opposite directions from promoters in a regulatory region located between the two structural genes [21].

Analytical, diagnostic and therapeutic context of tetR

• A quantitative real-time PCR assay for the detection of tetR of Tn10 in Escherichia coli using SYBR Green and the Opticon [11].
• A differential scanning calorimetry study of tetracycline repressor [22].

References