scholarly journals OmpR, a response regulator of the two-component signal transduction pathway, influences inv gene expression in Yersinia enterocolitica O9

2012 ◽  
Vol 2 ◽  
Author(s):  
Marta Brzóstkowska ◽  
Adrianna Raczkowska ◽  
Katarzyna Brzostek
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Yersinia Enterocolitica ◽  
Response Regulator ◽  
Signal Transduction Pathway ◽  
Transduction Pathway ◽  
Two Component ◽  
Two Component Signal Transduction

scholarly journals Copper Response Element and Crr1-Dependent Ni2+-Responsive Promoter for Induced, Reversible Gene Expression in Chlamydomonas reinhardtii

2003 ◽  
Vol 2 (5) ◽  
pp. 995-1002 ◽  
Author(s):  
Jeanette M. Quinn ◽  
Janette Kropat ◽  
Sabeeha Merchant
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Chlamydomonas Reinhardtii ◽  
Target Genes ◽  
Response Regulator ◽  
Signal Transduction Pathway ◽  
Transduction Pathway ◽  
Nickel Ions ◽  
Cobalt Ions ◽  
Inducible Gene

ABSTRACT The Cpx1 and Cyc6 genes of Chlamydomonas reinhardtii are activated in copper-deficient cells via a signal transduction pathway that requires copper response elements (CuREs) and a copper response regulator defined by the CRR1 locus. The two genes can also be activated by provision of nickel or cobalt ions in the medium. The response to nickel ions requires at least one CuRE and also CRR1 function, suggesting that nickel interferes with a component in the nutritional copper signal transduction pathway. Nickel does not act by preventing copper uptake/utilization because (i) holoplastocyanin formation is unaffected in Ni2+-treated cells and (ii) provision of excess copper cannot reverse the Ni-dependent activation of the target genes. The CuRE is sufficient for conferring Ni-responsive expression to a reporter gene, which suggests that the system has practical application as a vehicle for inducible gene expression. The inducer can be removed either by replacing the medium or by chelating the inducer with excess EDTA, either of which treatments reverses the activation of the target genes.

scholarly journals Identification of a Two-Component Signal Transduction System fromCorynebacterium diphtheriae That Activates Gene Expression in Response to the Presence of Heme and Hemoglobin

1999 ◽  
Vol 181 (17) ◽  
pp. 5330-5340 ◽  
Author(s):  
Michael P. Schmitt
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Response Regulator ◽  
Open Reading Frames ◽  
Sensor Kinase ◽  
Dependent Manner ◽  
Signal Transduction System ◽  
Kinase Gene ◽  
Two Component ◽  
Two Component Signal Transduction

ABSTRACT Corynebacterium diphtheriae, the causative agent of diphtheria, utilizes various host compounds to acquire iron. TheC. diphtheriae hmuO gene encodes a heme oxygenase that is involved in the utilization of heme and hemoglobin as iron sources. Transcription of the hmuO gene in C. diphtheriae is controlled under a dual regulatory mechanism in which the diphtheria toxin repressor protein (DtxR) and iron repress expression while either heme or hemoglobin is needed to activate transcription. In this study, two clones isolated from a C. diphtheriae chromosomal library were shown to activate transcription from the hmuO promoter in Escherichia coli. Sequence analysis revealed that these activator clones each carried distinct genes whose products had significant homology to response regulators of two-component signal transduction systems. Located upstream from each of these response regulator homologs are partial open reading frames that are predicted to encode the C-terminal portions of sensor kinases. The full-length sensor kinase gene for each of these systems was cloned from the C. diphtheriaechromosome, and constructs each carrying one complete sensor kinase gene and its cognate response regulator were constructed. One of these constructs, pTSB20, which carried the response regulator (chrA) and its cognate sensor kinase (chrS), was shown to strongly activate transcription from the hmuOpromoter in a heme-dependent manner in E. coli. A mutation in chrA (chrAD50N), which changed a conserved aspartic acid residue at position 50, the presumed site of phosphorylation by ChrS, to an asparagine, abolished heme-dependent activation. These findings suggest that the sensor kinase ChrS is involved in the detection of heme and the transduction of this signal, via a phosphotransfer mechanism, to the response regulator ChrA, which then activates transcription of the hmuO promoter. This is the first report of a bacterial two-component signal transduction system that controls gene expression through a heme-responsive mechanism.

scholarly journals Histidine Phosphotransfer Proteins in Fungal Two-Component Signal Transduction Pathways

2013 ◽  
Vol 12 (8) ◽  
pp. 1052-1060 ◽  
Author(s):  
Jan S. Fassler ◽  
Ann H. West
Keyword(s):  
Signal Transduction ◽  
Response Regulator ◽  
Single Gene ◽  
Signal Transduction Pathway ◽  
Pathogenic Fungi ◽  
Kinase Gene ◽  
Content Type ◽  
Two Component ◽  
Two Component Signal Transduction ◽  
Histidine Phosphotransfer

ABSTRACTThe histidine phosphotransfer (HPt) protein Ypd1 is an important participant in theSaccharomyces cerevisiaemultistep two-component signal transduction pathway and, unlike the expanded histidine kinase gene family, is encoded by a single gene in nearly all model and pathogenic fungi. Ypd1 is essential for viability in bothS. cerevisiaeand inCryptococcus neoformans. These and other aspects of Ypd1 biology, combined with the availability of structural and mutational data inS. cerevisiae, suggest that the essential interactions between Ypd1 and response regulator domains would be a good target for antifungal drug development. The goal of this minireview is to summarize the wealth of data onS. cerevisiaeYpd1 and to consider the potential benefits of conducting related studies in pathogenic fungi.

scholarly journals P Pilus Assembly Motif Necessary for Activation of the CpxRA Pathway by PapE in Escherichia coli

2004 ◽  
Vol 186 (13) ◽  
pp. 4326-4337 ◽  
Author(s):  
Yvonne M. Lee ◽  
Patricia A. DiGiuseppe ◽  
Thomas J. Silhavy ◽  
Scott J. Hultgren
Keyword(s):  
Escherichia Coli ◽  
Signal Transduction ◽  
Signal Transduction Pathway ◽  
The Self ◽  
Carboxyl Terminus ◽  
Transduction Pathway ◽  
Two Component ◽  
Pilus Biogenesis ◽  
Two Component Signal Transduction ◽  
Self Association

ABSTRACT P pilus biogenesis occurs via the highly conserved chaperone-usher pathway, and assembly is monitored by the CpxRA two-component signal transduction pathway. Structural pilus subunits consist of an N-terminal extension followed by an incomplete immunoglobulin-like fold that is missing a C-terminal seventh beta strand. In the pilus fiber, the immunoglobulin-like fold of each pilin is completed by the N-terminal extension of its neighbor. Subunits that do not get incorporated into the pilus fiber are driven “OFF-pathway.” In this study, we found that PapE was the only OFF-pathway nonadhesin P pilus subunit capable of activating Cpx. Manipulation of the PapE structure by removing, relocating within the protein, or swapping its N-terminal extension with that of other subunits altered the protein's self-associative and Cpx-activating properties. The self-association properties of the new subunits were dictated by the specific N-terminal extension provided and were consistent with the order of the subunits in the pilus fiber. However, these aggregation properties did not directly correlate with Cpx induction. Cpx activation instead correlated with the presence or absence of an N-terminal extension in the PapE pilin structure. Removal of the N-terminal extension of PapE was sufficient to abolish Cpx activation. Replacement of an N-terminal extension at either the amino or carboxyl terminus restored Cpx induction. Thus, the data presented in this study argue that PapE has features inherent in its structure or during its folding that act as specific inducers of Cpx signal transduction.

scholarly journals Dissecting the VanRS Signal Transduction Pathway with Specific Inhibitors

1999 ◽  
Vol 181 (2) ◽  
pp. 627-631 ◽  
Author(s):  
Andrew T. Ulijasz ◽  
Bernard Weisblum
Keyword(s):  
Signal Transduction ◽  
Pseudomonas Aeruginosa ◽  
Transcriptional Activation ◽  
Signal Transduction Pathway ◽  
Phosphoryl Transfer ◽  
Transduction Pathway ◽  
Two Component ◽  
Two Component Signal Transduction ◽  
Specific Inhibitors

ABSTRACT The VanRS two-component signal transduction pathway fromEnterococcus faecium was reconstituted in vitro from partially purified components and shown to be inhibited by the halophenyl isothiazolone LY-266,400, inhibitor A, a compound shown previously to reduce expression of the AlgR1-AlgR2 two-component signal transduction pathway in Pseudomonas aeruginosa (S. Roychoudhury, N. A. Zielinski, A. J. Ninfa, N. E. Allen, L. N. Jungheim, T. I. Nicas, and A. M. Chakrabarty, Proc. Natl. Acad. Sci. USA 90:965–969, 1993). Inhibitor A attenuates phosphoryl transfer from VanS∼P to VanR by its action on the ability of VanR to accept. We observed an apparent stimulatory effect of inhibitor A on VanS autophosphorylation which is attributable to the accumulation of VanS∼P as an intermediate unable to transfer Pi to the inhibited VanR. Thus, inhibitor A acts on the second of two sequential steps which lead to transcriptional activation of the VanHAXYZ gene cluster and the resultant expression of vancomycin resistance.

scholarly journals A Two-component Signal Transduction Pathway Regulates Manganese Homeostasis inSynechocystis6803, a Photosynthetic Organism

2002 ◽  
Vol 277 (32) ◽  
pp. 28981-28986 ◽  
Author(s):  
Teruo Ogawa ◽  
Ding Hui Bao ◽  
Hirokazu Katoh ◽  
Mari Shibata ◽  
Himadri B. Pakrasi ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Signal Transduction Pathway ◽  
Transduction Pathway ◽  
Two Component ◽  
Photosynthetic Organism ◽  
Two Component Signal Transduction

scholarly journals Differential Expression of the CO2 Fixation Operons of Rhodobacter sphaeroides by the Prr/Reg Two-Component System during Chemoautotrophic Growth

2002 ◽  
Vol 184 (23) ◽  
pp. 6654-6664 ◽  
Author(s):  
Janet L. Gibson ◽  
James M. Dubbs ◽  
F. Robert Tabita
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Cytochrome Oxidase ◽  
Rhodobacter Sphaeroides ◽  
Rhodobacter Capsulatus ◽  
Response Regulator ◽  
Signal Transduction Pathway ◽  
Pentose Phosphate ◽  
Bisphosphate Carboxylase

ABSTRACT In Rhodobacter sphaeroides, the two cbb operons encoding duplicated Calvin-Benson Bassham (CBB) CO2 fixation reductive pentose phosphate cycle structural genes are differentially controlled. In attempts to define the molecular basis for the differential regulation, the effects of mutations in genes encoding a subunit of Cbb3 cytochrome oxidase, ccoP, and a global response regulator, prrA (regA), were characterized with respect to CO2 fixation (cbb) gene expression by using translational lac fusions to the R. sphaeroides cbb I and cbbII promoters. Inactivation of the ccoP gene resulted in derepression of both promoters during chemoheterotophic growth, where cbb expression is normally repressed; expression was also enhanced over normal levels during phototrophic growth. The prrA mutation effected reduced expression of cbbI and cbbII promoters during chemoheterotrophic growth, whereas intermediate levels of expression were observed in a double ccoP prrA mutant. PrrA and ccoP1 prrA strains cannot grow phototrophically, so it is impossible to examine cbb expression in these backgrounds under this growth mode. In this study, however, we found that PrrA mutants of R. sphaeroides were capable of chemoautotrophic growth, allowing, for the first time, an opportunity to directly examine the requirement of PrrA for cbb gene expression in vivo under growth conditions where the CBB cycle and CO2 fixation are required. Expression from the cbbII promoter was severely reduced in the PrrA mutants during chemoautotrophic growth, whereas cbbI expression was either unaffected or enhanced. Mutations in ccoQ had no effect on expression from either promoter. These observations suggest that the Prr signal transduction pathway is not always directly linked to Cbb3 cytochrome oxidase activity, at least with respect to cbb gene expression. In addition, lac fusions containing various lengths of the cbbI promoter demonstrated distinct sequences involved in positive regulation during photoautotrophic versus chemoautotrophic growth, suggesting that different regulatory proteins may be involved. In Rhodobacter capsulatus, ribulose 1,5-bisphosphate carboxylase-oxygenase (RubisCO) expression was not affected by cco mutations during photoheterotrophic growth, suggesting that differences exist in signal transduction pathways regulating cbb genes in the related organisms.

Histidine kinases in signal transduction pathways of eukaryotes

1997 ◽  
Vol 110 (10) ◽  
pp. 1141-1145 ◽  
Author(s):  
W.F. Loomis ◽  
G. Shaulsky ◽  
N. Wang
Keyword(s):  
Signal Transduction ◽  
Response Regulator ◽  
Signal Transduction Pathways ◽  
Response Regulators ◽  
Histidine Kinases ◽  
Camp Phosphodiesterase ◽  
Wide Range ◽  
Two Component ◽  
Two Component Signal Transduction ◽  
Dependent Protein

Autophosphorylating histidine kinases are an ancient conserved family of enzymes that are found in eubacteria, archaebacteria and eukaryotes. They are activated by a wide range of extracellular signals and transfer phosphate moieties to aspartates found in response regulators. Recent studies have shown that such two-component signal transduction pathways mediate osmoregulation in Saccharomyces cerevisiae, Dictyostelium discoideum and Neurospora crassa. Moreover, they play pivotal roles in responses of Arabidopsis thaliana to ethylene and cytokinin. A transmembrane histidine kinase encoded by dhkA accumulates when Dictyostelium cells aggregate during development. Activation of DhkA results in the inhibition of its response regulator, RegA, which is a cAMP phosphodiesterase that regulates the cAMP dependent protein kinase PKA. When PKA is activated late in the differentiation of prespore cells, they encapsulate into spores. There is evidence that this two-component system participates in a feedback loop linked to PKA in prestalk cells such that the signal to initiate encapsulation is rapidly amplified. Such signal transduction pathways can be expected to be found in a variety of eukaryotic differentiations since they are rapidly reversible and can integrate disparate signals.

Sign in / Sign up

Export Citation Format

Share Document