Curation Information

Publication: Arginine-dependent gene regulation via the ArgR repressor is species specific in chlamydia.;Schaumburg CS, Tan M;Journal of bacteriology 2006 Feb; 188(3):919-27 [16428395]
TF: ArgR [Q9Z8Z1, view regulon]
Reported TF sp.: Chlamydophila pneumoniae CWL029
Reported site sp.: Chlamydophila pneumoniae CWL029
Created by: Dinara Sagitova
Curation notes: -

Experimental Process

An ArgR binding site in glnPQ upstream region was predicted via a bioinformatics approach in a previous study. In this publication, EMSA confirmed that ArgR specifically bound to the glnPQ promoter in the presence of L-arginine. In vitro transcription assay showed that ArgR represses transcription of the glnPQ promoter.

Transcription Factor Binding Sites

Sites reported in the paper
Sites matched in the genome

ATTGCATAAATATGATTT
TATAAATAAATATGCATA

Gene Regulation

Regulated genes for each binding site are displayed below. Gene regulation diagrams show binding sites, positively-regulated genes, negatively-regulated genes, both positively and negatively regulated genes, genes with unspecified type of regulation. For each indvidual site, experimental techniques used to determine the site are also given.

Site sequence	Regulated genes	Gene diagram	Experimental techniques	TF function	TF type
ATTGCATAAATATGATTT	glnP, glnQ,		Experimental technique details EMSA (ECO:0001807) EMSA - ECO:0001807 Electro-mobility shift-assays (or gel retardation assays) are a standard way of assessing TF-binding. A fragment of DNA of interest is amplified and labeled with a fluorophore. The fragment is left to incubate in a solution containing abundant TF and non-specific DNA (e.g. randomly cleaved DNA from salmon sperm, of all things) and then a gel is run with the incubated sample and a control (sample that has not been in contact with the TF). If the TF has bound the sample, the complex will migrate more slowly than unbound DNA through the gel, and this retarded band can be used as evidence of binding. The unspecific DNA ensures that the binding is specific to the fragment of interest and that any non-specific DNA-binding proteins left-over in the TF purification will bind there, instead of on the fragment of interest. EMSAs are typically carried out in a bunch of fragments, shown as multiple double (control+experiment) lanes in a wide picture. Certain additional controls are run in at least one of the fragments to ascertain specificity. In the most basic of these, specific competitor (the fragment of interest or a known positive control, unlabelled) is added to the reaction. This should sequester the TF and hence make the retardation band disappear, proving that the binding is indeed specific - Experimental technique details In-vitro transcription (ECO:0001204) In-vitro transcription - ECO:0001204 In-vitro transcription is often used to validate that a particular TF can or cannot activate/repress a gene in the absence of other proteins that are present in in vivo conditions. -	repressor	not specified
TATAAATAAATATGCATA	glnP, glnQ		Experimental technique details EMSA (ECO:0001807) EMSA - ECO:0001807 Electro-mobility shift-assays (or gel retardation assays) are a standard way of assessing TF-binding. A fragment of DNA of interest is amplified and labeled with a fluorophore. The fragment is left to incubate in a solution containing abundant TF and non-specific DNA (e.g. randomly cleaved DNA from salmon sperm, of all things) and then a gel is run with the incubated sample and a control (sample that has not been in contact with the TF). If the TF has bound the sample, the complex will migrate more slowly than unbound DNA through the gel, and this retarded band can be used as evidence of binding. The unspecific DNA ensures that the binding is specific to the fragment of interest and that any non-specific DNA-binding proteins left-over in the TF purification will bind there, instead of on the fragment of interest. EMSAs are typically carried out in a bunch of fragments, shown as multiple double (control+experiment) lanes in a wide picture. Certain additional controls are run in at least one of the fragments to ascertain specificity. In the most basic of these, specific competitor (the fragment of interest or a known positive control, unlabelled) is added to the reaction. This should sequester the TF and hence make the retardation band disappear, proving that the binding is indeed specific - Experimental technique details In-vitro transcription (ECO:0001204) In-vitro transcription - ECO:0001204 In-vitro transcription is often used to validate that a particular TF can or cannot activate/repress a gene in the absence of other proteins that are present in in vivo conditions. -	repressor	not specified