Transcription profiling of chromosome 22 genes in human peripheral blood mononuclear cells after stimulation with HIV-gag and env peptides
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ABSTRACT: Comparison of expression levels of the genes on chromosome 22 in the peripheral blood mononuclear cells at various time points after stimulation with HIV-gag and env peptides
Project description:Integration host factor (IHF) sites are largely absent from intergenic regions of ORFs encoding central metabolic functions in Pseudomonas putida mt-2. To gain an insight into this unequal distribution of otherwise abundant IHF-binding sequences, the transcriptome of IHF-plus and IHF-minus cells growing exponentially on glucose as sole carbon source was examined. In parallel, the cognate metabolic fluxes of the wild-type P. putida strain and its ihfA derivative were determined by culturing cells to a steady-state physiological regime with (13) C-labelled glucose. While expression of many transcripts was altered by the lack of IHF, flux balance analysis revealed that the ihfA mutation did not influence central carbon metabolism. Identification of multiple IHF sites adjacent to genes responsive to the factor allowed a refinement of the consensus and the mapping of the preferred binding positions for activation or repression of associated promoters. That few (if any) of the genes affected by IHF involved core pathways suggested that the central carbon metabolism tolerates the loss of the factor. Instead, IHF controlled various cell surface-related functions and downregulated genes encoding ribosomal proteins, the alpha subunit of RNA polymerase and components of the ATP synthase. These results were confirmed with lacZ fusions to a suite of promoters detected in the transcriptome as affected by IHF. Taken together, the data suggest that IHF plays a role in the physiological shift that sets P. putida for entering stationary phase. We compared the transcriptional profiles of P. putida mt-2 and the ihfA mutant. Samples were hybridized on a P. putida genome-wide oligonucleotide-based DNA microarray (Progenika Biopharma SA). RNA samples of seven independent biological samples were mixed in three pools. A dye-swap was performed.
Project description:The genomic and proteomic analyses of Streptomyces lividans strains deficient in the major signal peptidase SipY or in the translocase complex protein SecG resulted in a set of genes being equally regulated. These genes are apparently responsible for the common deficiencies in extracellular protein production and sporulation shared by both mutant strains, constituting a cellular response to the stress caused by the potential malfunction of the translocase complex, which we have named M-bM-^@M-^\extracellular protein translocation stress (EPTS)M-bM-^@M-^]. All microarray analyses were performed with RNA samples obtained from three independent cultures grown under identical conditions. The cDNA obtained from each RNA preparation of the SipY-deficient strain or the SecG-deficient strain were hybridised with the cDNA obtained from the equivalent RNA preparation of the wild type strain (S. lividans TK21).
Project description:The Streptomyces coelicolor two genes operon SCO5784-SCO5785 encodes a two-component system which functions in a similar manner to that of the Bacillus subtilis DegS-DegU system. Propagation of the regulatory gene in high copy number results in the overproduction of several extracellular enzymes, among them the major extracellular protease, as well as in a higher level of synthesis of the antibiotic actinorhodin. This two-component system seems to control various processes characterised by the transition from primary to secondary metabolism in S. coelicolor, as determined by proteomic and transcriptomic analices. The presence of the regulatory gene in high copy number in S. coelicolor additionally seems to elicit a stringent response in the bacterial cell. Therefore, we propose renaming S. coelicolor genes SCO5784 and SCO5785 as degS and degU, respectively. All microarray analyses were performed with RNA samples obtained from three independent cultures grown under identical conditions. Hybridisation assays were carried out with cDNA obtained from RNA extracted at the late exponential phase of growth (24h). The transcriptional profile of wild type (S. coelicolor M145) cells carrying the multicopy plasmid pIJ487 was compared with that of the same strain carrying the degU gene cloned in the same plasmid under the control of its own promoter (S. coelicolor M28). And the transcriptional profile of wild type (S, coelicolor M145) cells was compared to that of the DegU deficient strain (S. coelicolor I32).
Project description:The Streptomyces lividans lsp gene encodes a type II signal peptidase (Lsp) that cleaves the type II leader peptides of lipoproteins. Transcriptional profiling of the bacterium depleted of the lsp gene mainly resulted in deactivation of the sigma U regulon, as well as in downregulation of genes involved in the biogenesis and function of ribosomes and genes encoding some major secretory proteins as determined by hybridisation of commercially available S. lividans genome-wide microarrays. Almost 50% of the dowregulated genes have been described as forming part of the stringent response in streptomycetes. The gene encoding the S. lividans extracellular foldase, the lipoprotein FkpA, is equally downregulated. Therefore, the deletion of lsp from the S. livdans genome temporarily triggers a cellular stress where the stringent response is, at least, partially induced. All microarray analyses were performed with RNA samples obtained from three independent cultures grown under identical conditions. The cDNA obtained from each RNA preparation of the Lsp-deficient strain was hybridised with the cDNA obtained from the equivalent RNA preparation of the wild type strain (S. lividans TK21).
Project description:The gene aml encoding alpha-amylase in Streptomyces lividans was cloned in the multicopy plasmid pIJ486, generating plasmid pAMI11. Plasmid pAMI11 and pIJ486 were propagated in S. lividans TK21 to obtain S. lividans TK21(pAMI11) and its isogenic strain S. lividans TK21(pIJ486). Transcriptional profiling of the bacterium that overproduces alpha-amylase mainly resulted in the upregulation of genes involved in the biogenesis and function of ribosomes, together with the upregulation of the genes involved in the redox processes, the ABC transporters, the central carbon, aminoacid and purine /pyrimidine metabolism. Moreover, some genes involved in oxidative stress were upregulated. The number of genes downregulated was much lower than the upregulated ones. Therefore, bacteria respond by favouring alpha-amylase overproduction that apparently does not cause damage to the cell. All microarray analyses were performed with RNA samples obtained from three independent cultures grown under identical conditions. The cDNA obtained from each RNA preparation of the alpha-amylase overproducer strain was hybridised with the cDNA obtained from the equivalent RNA preparation of the isogenic strain (S. lividans TK21 [pIJ486]).
Project description:The gene dagA encoding agarase in Streptomyces coelicolor was cloned in the multicopy plasmid pIJ486 generating plasmid pAGAs5. Plasmid pAGAs5 and pIJ486 were propagated in S. lividans TK21 to obtain S. lividans TK21(pAGAs5) and its isogenic strain S. lividans TK21(pIJ486). Transcriptional profiling of the bacterium that overproduces agarase mainly resulted in the downregulation of the genes involved in the biogenesis and function of ribosomes, together with the downregulation of the genes involved in nitrogen, aminoacids, purine/pyrimidine and central carbon metabolism as well as ABC transporters, redox processes and fatty acids biosynthesis. The number of genes upregulated in the agarase overproducer strain is lower than in the downregulated ones. Almost 50% of the dowregulated genes have been described as forming part of the stringent response in streptomycetes. Therefore, the overproduction of agarase may lead to a condition of nutrient depletion that triggers the stringent response. All microarray analyses were performed with RNA samples obtained from three independent cultures grown under identical conditions. The cDNA obtained from each RNA preparation of the agarase overproducer strain was hybridised with the cDNA obtained from the equivalent RNA preparation of the isogenic strain (S. lividans TK21 [pIJ486]).