To identify YehT-regulated genes, the transcriptome profiles of E. coli cells overproducing either the response regulator (RR) YehT or the RR KdpE (control) were comparatively analyzed. The expression level of 32 genes varied more than 8-fold.
First insights into the unexplored two-component system YehU/YehT in Escherichia coli
No sample metadata fields
View SamplesTo identify YpdB-regulated genes, the transcriptome profiles of E. coli cells overproducing either the response regulator (RR) YpdB or the RR YehS (control) were comparatively analyzed. The expression level of 15 genes varied more than 1.9-fold.
Identification of a target gene and activating stimulus for the YpdA/YpdB histidine kinase/response regulator system in Escherichia coli
No sample metadata fields
View SamplesDynamic transcriptome profiling with metabolic labeling (4tU) (Sun et al. Genome Research 2012) was applied to synchronized S.cerevisiae cells to estimate labeled and total mRNA levels every 5 minutes for three complete cell cycles. The dataset comprises two time series from independent biological replicates for each mRNA fraction (total, labeled).
Periodic mRNA synthesis and degradation co-operate during cell cycle gene expression
Sex, Treatment, Time
View SamplesRNA polymerase II (Pol II) is the central enzyme that carries out eukaryotic mRNA transcription and consists of a 10-subunit catalytic core and a heterodimeric subcomplex of subunits Rpb4 and Rpb7 (Rpb4/7). Rpb4/7 has been proposed to shuttle from the nucleus to the cytoplasm, and to function there in mRNA translation and degradation. Here we provide evidence that Rpb4 mainly functions in nuclear mRNA synthesis by Pol II, and evidence arguing against an important cytoplasmic role. We used metabolic RNA labeling and comparative Dynamic Transcriptome Analysis (cDTA) to show that Rpb4 deletion in Saccharomyces cerevisiae causes a drastic defect in mRNA synthesis that is compensated by down-regulation of mRNA degradation, resulting in mRNA level buffering. Deletion of Rpb4 can be rescued by covalent fusion of Rpb4 to the Pol II core subunit Rpb2, which largely restores mRNA synthesis and degradation defects caused by Rpb4 deletion. Thus Rpb4 is a bona fide Pol II core subunit which functions mainly in mRNA synthesis.
Rpb4 functions mainly in mRNA synthesis by RNA polymerase II
Sex
View SamplesBy applying MC EMiNEM (a novel method based on the concept of Nested Effects Models (NEMs) for the retrieval of functional dependencies between proteins that have pleiotropic effects on mRNA transcription) to the expression data from four gene perturbation studies (three of them unpublished) in Saccharomyces cerevisiae, we hope to derive new insight into the Mediator signaling network and specific transcription factor - Mediator subunit interactions. The structure of the resulting regulatory networks allows us to hypothesize on possible structural changes of the Mediator upon binding of activators or repressors.
MC EMiNEM Maps the Interaction Landscape of the Mediator
Sex
View SamplesSaccharomyces cerevisiae strains carrying mutations of the essential Mediator subunit Med11 as well as strains lacking the non-essential Mediator subunits Med2 and Med20 were compared to the corresponding wild-type strains.
Mediator head subcomplex Med11/22 contains a common helix bundle building block with a specific function in transcription initiation complex stabilization
Sex, Subject
View SamplesEngineering of genetically encoded calcium indicators predominantly focused on optimizing fluorescence changes, but effects of indicator expression on host organisms have largely not been addressed. Here, we report biocompatibility and wide-spread functional expression of the genetically encoded calcium indicator TN-XXL in a transgenic mouse model. To validate the model and to characterize potential effects of indicator expression we assessed both indicator function and a variety of host parameters such as anatomy, physiology, behavior and gene expression profiles in these mice. We also demonstrate the usefulness of primary cell types and organ explants prepared from these mice for imaging applications. While we do find mild signatures of indicator expression that may guide further indicator development the green indicator mice generated provide a well characterized resource of primary cells and tissues for in vitro and in vivo calcium imaging applications.
Biocompatibility of a genetically encoded calcium indicator in a transgenic mouse model.
Specimen part
View SamplesTertiary lymphoid organs (TLOs) emerge in response to nonresolving inflammation but their roles in adaptive immunity remain unknown. Here, we explored artery TLOs (ATLOs) to delineate atherosclerosis T cell responses in apoe-/- mice during aging. Though the T cell repertoire showed systemic age-associated contractions in size and modifications in subtype composition and activation, wt and apoe-/- mice were equally affected. In contrast, ATLOs - but not wt aortae, apoe-/- aorta segments without ATLOs or atherosclerotic plaques - promoted T cell recruitment, altered characteristics of T cell motility, primed and imprinted T cells in situ, generated CD4+/FoxP3-, CD4+/FoxP3+, CD8+/FoxP3- effector and central memory cells, and converted nave CD4+/FoxP3- T cells into induced Treg cells. ATLOs also showed substantially increased antigen presentation capability by conventional dendritic cells (DCs) and monocyte-derived DCs but not by plasmacytoid DCs. Thus, the senescent immune system specifically employs ATLOs to control dichotomic atherosclerosis T cell immune responses. We assembled transcriptome maps of wt and apoe-/- aortae and aorta-draining RLNs and identified ATLOs as major sites of atherosclerosis-specific T cell responses during aging: Transcriptome atlases of wt and apoe-/- abdominal aortae and associated draining RLNs were constructed from laser capture microdissection (LCM)-based whole genome mRNA expression microarrays yielding 6 maps: wt adventitia (tissue-1); wt RLN (tissue-2); apoe-/- ATLOs (tissue-3); apoe-/- RLN (tissue-4); apoe-/- adventitia without adjacent plaques (tissue-5), and plaques (tissue-6). Several two-tissue comparisons within the transcriptome atlases are noteworthy: Unexpectedly, transcriptomes of wt and apoe-/- RLNs were virtually identical; additonal data revealed that transcriptomes of RLNs were strikingly similar to those of inguinal LNs which do not drain the aorta adventitia (as shown of India ink injection experiments of surgically exposed aortae); in sharp contrast, wt adventitia versus ATLOs revealed 1405 differentially expressed transcripts many of which encoded members of GO terms immune response and inflammatory response; the ATLO-plaque comparison also showed > 1000 differentially expressed transcripts; however, wt adventitia versus apoe-/- adventitia without plaque showed few genes (< 5 % of differentially expressed transcripts of the wt adventitia-ATLO comparison). Thus, the aorta transcriptome atlases support the conclusion that neither aorta-draining apoe-/- RLNs nor ILNs participate in atherosclerosis-specific T cell responses. In addition, they demonstrate that T cell responses in the diseased aorta are highly territorialized. Finally, these data show that the immune responses carried out in ATLOs differ significantly from those carried out in plaques. We next identified three major clusters within the transcriptome atlases through ANOVA analyses and application of strict filters: An adventitia cluster, a plaque/ATLO cluster, and a LN/plaque cluster. The total number of differentially expressed genes in each cluster were examined for GO terms immune response, inflammatory response, T cell activation, positive regulation of T cell response, and T cell proliferation. Within the adventitia cluster, similarities of transcriptomes of wt adventitia and apoe-/- adventitia without associated plaque versus ATLOs indicate that a robust number of immune response-regulating genes are selectively expressed in ATLOs which are located within a distance of few m of the adventitia without associated plaques indicating a very high degree of territoriality of the atherosclerosis T cell response. Furthermore, unlike the total number of differentially regulated transcripts, the majority of transcripts among GO terms immune response and inflammatory response, was up-regulated. Inspection of the plaque/ATLO cluster provided further information: The majority of immune response regulating genes where expressed at a higher level in ATLOs when compared to plaques though plaques also contained a significant number of immune response regulating genes; the reverse is true for genes regulating inflammation. Finally, the lymph node cluster revealed that though the majority of immune response regulating genes resides in both wt and apoe-/- RLNs (with little differences between them) ATLOs express a selected set of immune response regulating genes at a higher level when compared to LNs. In addition, the inflammatory component of ATLOs when compared to LNs is documented by the finding that many more genes regulating inflammation reside in ATLOs even when compared to those of plaques.
Generation of Aorta Transcript Atlases of Wild-Type and Apolipoprotein E-null Mice by Laser Capture Microdissection-Based mRNA Expression Microarrays.
Sex, Age, Specimen part
View SamplesAnalysis of differential gene expression for rutured vs stable abdominal aortic aneurysms (AAA) and for intermediate size (55mm) vs large (>70mm) AAA.
Molecular Fingerprint for Terminal Abdominal Aortic Aneurysm Disease.
Specimen part
View SamplesColonization of barley roots with the basidiomycete fungus Piriformospora indica enhances resistance against the leaf pathogen Blumeria graminis f.sp. hordei (Bgh). To identify genes involved in this mycorrhiza-induced systemic resistance, we used the Affymetrix Barley1 22K gene chip for leaf transcriptome analysis of P. indica-colonized and non-colonized barley plants 12, 24 and 96 hours post inoculation (hpi) with a compatible Bgh strain.
No associated publication
Age, Specimen part, Disease, Disease stage
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