Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Escherichia coli Lrp regulates one-third of the genome via direct, cooperative, and indirect paths

ABSTRACT: The global regulator Lrp plays a crucial role in regulating metabolism, virulence and motility in response to environmental conditions. Lrp has previously been shown to activate or repress approximately 10% of genes in Escherichia coli. However, the full spectrum of targets, and how Lrp acts to regulate them, has stymied earlier study. We have combined matched ChIP-seq and RNA sequencing under nine physiological conditions to map the binding and regulatory activity of Lrp as it directs responses to nutrient abundance. In addition to identifying hundreds of novel Lrp targets, we observe two new global trends: first, that Lrp will often bind to promoters in a poised position under conditions when it has no regulatory activity, and second, that nutrient levels induce a global shift in the equilibrium between non-specific and sequence-specific DNA binding. The overall regulatory behavior of Lrp, which as we now show regulates 35% of E. coli genes directly or indirectly under at least one condition, thus arises from the interaction between changes in Lrp binding specificity and cooperative action with other regulators.

ORGANISM(S): Escherichia coli

PROVIDER: GSE111874 | GEO | 2018/11/28

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

High throughput analysis of binding of E. coli Lrp mutants

Project description:Feast-Famine Response Proteins are a widely conserved class of global regulators in prokaryotes, the most highly studied of which is the E. coli leucine-responsive regulatory protein (Lrp). Lrp senses environmental nutrition status and subsequently regulates up to one-third of the genes in E. coli, either directly or indirectly. Lrp exists predominantly as octamers and hexadecamers (16mers), where leucine is believed to shift the equilibrium towards the octameric state. In this study, we analyzed the effects of three oligomerization state mutants of Lrp in terms of their ability to bind to DNA and regulate gene expression in response to exogenous leucine. We find that oligomerization beyond dimers is required for Lrp’s regulatory activity, and that contrary to prior speculation, exogenous leucine modulates Lrp activity at its target promoters exclusively by inhibiting Lrp binding to DNA. We also find evidence that Lrp binding bridges DNA over length scales of multiple kilobases, revealing a new range of mechanisms for Lrp-mediated transcriptional regulation.

2023-01-31 | GSE198120 | GEO

Transcription profiling of sogenic Lrp(+) and Lrp(-) strains in cells growing in steady state in glucose minimal medium, either in the presence or absence of leucine. (Adaptation to famine)

Project description:Bacterial adaptation to nutrient limitation and increased population densities is central to survival and virulence. Surprisingly, <3% of Escherichia coli genes are known to play roles specific to the stationary phase. There is evidence that the leucine-responsive regulatory protein (Lrp) may play an important role in stationary phase, so this study used microarrays representing >98% of E. coli genes to more comprehensively identify those controlled by Lrp. The primary analysis compared isogenic Lrp(+) and Lrp(-) strains in cells growing in steady state in glucose minimal medium, either in the presence or absence of leucine. More than 400 genes were significantly Lrp-responsive under the conditions used. Transcription of 147 genes was lower in Lrp(+) than in Lrp(-) cells whether or not leucine was present; most of these genes were tightly coregulated under several conditions, including a burst of synthesis on transition to stationary phase. This cluster includes 56 of 115 genes already known to play roles in stationary phase. Our results suggest that the actual number of genes induced on entrance into stationary phase is closer to 200 and that Lrp affects nearly three-quarters of them, including genes involved in response to nutrient limitation, high concentrations of organic acids, and osmotic stress.

2005-09-02 | E-SMDB-1726 | biostudies-arrayexpress

ChIP-chip of E. coli K-12 MG1655 with antibody against ArgR-8myc, Lrp-8myc, and TrpR-8myc under various conditions.

2011-12-01 | GSE26054 | GEO

ChIP-chip of E. coli K-12 MG1655 with antibody against ArgR-8myc, Lrp-8myc, and TrpR-8myc under various conditions.

Project description:We integrated transcription factor binding regions and mRNA transcript abundance to elucidate the ArgR, Lrp, and TrpR regulon experimentally. To measure transcription factor binding at a genome scale, we employed a ChIP-chip method to derivative strains of E. coli K-12 MG1655 harboring ArgR-8myc, Lrp-8myc, or TrpR-8myc under various conditions. A twelve ChIP-chip study under six separate culture conditions. The high-density oligonucleotide tiling arrays used were consisted of 371,034 oligonucleotide probes spaced 25 bp apart (25-bp overlap between two probes) across the E. coli genome.

2011-12-01 | E-GEOD-26054 | biostudies-arrayexpress

Adaptation to famine

2005-09-10 | GSE3283 | GEO

Adaptation to famine

2005-09-10 | E-GEOD-3283 | biostudies-arrayexpress

High throughput analysis of binding of E. coli Lrp mutants

Project description:High throughput analysis of binding of E. coli Lrp mutants

| PRJNA813682 | ENA

Influence of LRP-1 on MDA-MB-231 secretome

Project description:LRP-1 (low-density lipoprotein receptor-related protein-1) receptor is a multifunctional endocytosis receptor that is part of the LDL receptor family. Due to its capacity to control the pericellular level of various growth factors and proteases, LRP-1 plays a crucial role in controlling the dynamics of the membrane proteome. LRP-1 overexpression in breast cancer, prompted us to take an interest in its involvement in tumor progression. An RNA interference strategy in MDA-MB-231 line was used, based on shRNA stable expression. In addition to integrated experimental strategies (in vitro and in vivo) through combined approaches of biochemistry, molecular biology, cell biology, multimodal preclinical imaging, proteomics allowed us to compare shLRP-1 MDA-MB-231 tumor conditioned media to shCtrl MDA-MB-231 tumor conditioned media in order to identify secreted molecular targets modulate by LRP-1 repression and thus provide a better understanding of its regulatory action within the TNBC microenvironment.

2022-02-16 | PXD022978 | Pride

Escherichia coli Lrp regulates one-third of the genome via direct, cooperative, and indirect paths

Project description:Escherichia coli Lrp regulates one-third of the genome via direct, cooperative, and indirect paths

| PRJNA438455 | ENA

E. coli Isoleucine starvation and stringent response network

Project description:Transcription profiling of wild type, relA-, and relA-spoT-, crp-, dksA-, rpoS-, lrp- mutant strains of E. coli starved for isoleucine Bacteria comprehensively reorganize their global gene expression when faced with nutrient exhaustion. In Escherichia coli and other free-living bacteria, the alarmone ppGpp facilitates this massive response by directly or indirectly coordinating the down-regulation of genes of the translation apparatus, and the induction of biosynthetic genes and the general stress response. Such a large reorientation likely requires the cooperative activities of many different genetic regulators, yet the structure of the transcription network below the level of ppGpp remains poorly defined. Using isoleucine starvation as an experimental model system for amino acid starvation, we identified genes that required ppGpp, Lrp, and RpoS for their induction. Surprisingly, despite the fact that the overwhelming majority of genes controlled by Lrp and RpoS required ppGpp for their activation, we found that these two regulons were not induced simultaneously. The data reported here suggest that metabolic genes, such as those of the Lrp regulon, require only a low basal level of ppGpp for their efficient induction. In contrast, the RpoS-dependent general stress response is not robustly induced until relatively high levels of ppGpp accumulate. Here we describe a data-driven conceptual model that explains how bacterial cells allocate transcriptional resources between metabolic and stress survival processes by discretely tuning regulatory activities to a central indicator of cellular physiology. The regulatory structure that emerges is consistent with a rheostatic model of the stringent response that allows cells to efficiently adapt to a wide range of nutritional environments. Keywords: genetic modification design; stress response; isoleucine starvation

2008-04-08 | GSE11087 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data