scholarly journals Protein Kinase G Induces an Immune Response in Cows Exposed toMycobacterium aviumSubsp.paratuberculosis

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Horacio Bach ◽  
Melissa Richard-Greenblatt ◽  
Eviatar Bach ◽  
Marcelo Chaffer ◽  
Wanika Lai ◽  
...  

To establish infection, pathogens secrete virulence factors, such as protein kinases and phosphatases, to modulate the signal transduction pathways used by host cells to initiate immune response. The protein MAP3893c is annotated in the genome sequence ofMycobacterium aviumsubspeciesparatuberculosis(MAP), the causative agent of Johne’s disease, as the serine/threonine protein kinase G (PknG). In this work, we report that PknG is a functional kinase that is secreted within macrophages at early stages of infection. The antigen is able to induce an immune response from cattle exposed to MAP in the form of interferon gamma production after stimulation of whole blood with PknG. These findings suggest that PknG may contribute to the pathogenesis of MAP by phosphorylating macrophage signalling and/or adaptor molecules as observed with other pathogenic mycobacterial species.

2009 ◽  
Vol 53 (8) ◽  
pp. 3515-3519 ◽  
Author(s):  
Kerstin A. Wolff ◽  
Hoa T. Nguyen ◽  
Richard H. Cartabuke ◽  
Ajay Singh ◽  
Sam Ogwang ◽  
...  

ABSTRACT Antibiotic resistance and virulence of pathogenic mycobacteria are phenotypically associated, but the underlying genetic linkage has not been known. Here we show that PknG, a eukaryotic-type protein kinase previously found to support survival of mycobacteria in host cells, is required for the intrinsic resistance of mycobacterial species to multiple antibiotics.


2002 ◽  
Vol 13 (10) ◽  
pp. 3720-3729 ◽  
Author(s):  
Maria Marino ◽  
Filippo Acconcia ◽  
Francesco Bresciani ◽  
Alessandro Weisz ◽  
Anna Trentalance

Estrogens induce cell proliferation in target tissues by stimulating progression through the G1 phase of the cell cycle. Activation of cyclin D1 gene expression is a critical feature of this hormonal action. The existence of rapid/nongenomic estradiol-regulated protein kinase C (PKC-α) and extracellular signal-regulated kinase (ERK) signal transduction pathways, their cross talk, and role played in DNA synthesis and cyclin D1 gene transcription have been studied herein in human hepatoma HepG2 cells. 17β-Estradiol was found to rapidly activate PKC-α translocation and ERK-2/mitogen-activated protein kinase phosphorylation in this cell line. These actions were independent of each other, preceding the increase of thymidine incorporation into DNA and cyclin D1expression, and did not involve DNA binding by estrogen receptor. The results obtained with specific inhibitors indicated that PKC-α pathway is necessary to mediate the estradiol-induced G1-S progression of HepG2 cells, but it does not exert any effect(s) on cyclin D1 gene expression. On the contrary, ERK-2 cascade was strongly involved in both G1-S progression and cyclin D1gene transcription. Deletion of its activating protein-1 responsive element motif resulted in attenuation of cyclin D1 promoter responsiveness to estrogen. These results indicate that estrogen-induced cyclin D1 transcription can occur in HepG2 cells independently of the transcriptional activity of estrogen receptor, sustaining the pivotal role played by nongenomic pathways of estrogen action in hormone-induced proliferation.


2000 ◽  
Vol 20 (17) ◽  
pp. 6426-6434 ◽  
Author(s):  
Lori A. Neely ◽  
Charles S. Hoffman

ABSTRACT A significant challenge to our understanding of eukaryotic transcriptional regulation is to determine how multiple signal transduction pathways converge on a single promoter to regulate transcription in divergent fashions. To study this, we have investigated the transcriptional regulation of theSchizosaccharomyces pombe fbp1 gene that is repressed by a cyclic AMP (cAMP)-dependent protein kinase A (PKA) pathway and is activated by a stress-activated mitogen-activated protein kinase (MAPK) pathway. In this study, we identified and characterized twocis-acting elements in the fbp1 promoter required for activation of fbp1 transcription. Upstream activation site 1 (UAS1), located approximately 900 bp from the transcriptional start site, resembles a cAMP response element (CRE) that is the binding site for the atf1-pcr1 heterodimeric transcriptional activator. Binding of this activator to UAS1 is positively regulated by the MAPK pathway and negatively regulated by PKA. UAS2, located approximately 250 bp from the transcriptional start site, resembles a Saccharomyces cerevisiae stress response element. UAS2 is bound by transcriptional activators and repressors regulated by both the PKA and MAPK pathways, although atf1 itself is not present in these complexes. Transcriptional regulation offbp1 promoter constructs containing only UAS1 or UAS2 confirms that the PKA and MAPK regulation is targeted to both sites. We conclude that the PKA and MAPK signal transduction pathways regulatefbp1 transcription at UAS1 and UAS2, but that the antagonistic interactions between these pathways involve different mechanisms at each site.


Physiology ◽  
1988 ◽  
Vol 3 (6) ◽  
pp. 235-241 ◽  
Author(s):  
Y Ando ◽  
HR Jacobson ◽  
MD Breyer

Receptor-mediated signal transduction occurs through phosphatidylinositol bisphosphate (PIP2) breakdown and activation of adenylate cyclase interacting to regulate cell function. Current studies suggest that hormone-stimulated PIP2 breakdown modulates the classic cyclic AMP-mediated hydrosmotic action of vasopressin through separate mechanisms attributable to activation of protein kinase C, elevation of intracellular Ca2+ concentration, and generation of arachidonate metabolites.


2009 ◽  
Vol 157 (7) ◽  
pp. 1232-1240 ◽  
Author(s):  
Pilar Requena ◽  
Abdelali Daddaoua ◽  
Emilia Guadix ◽  
Antonio Zarzuelo ◽  
María Dolores Suárez ◽  
...  

1996 ◽  
Vol 24 (1) ◽  
pp. 69S-69S ◽  
Author(s):  
Sarah J. Turner ◽  
Stephen G. Ward ◽  
Murray McKinnon ◽  
John Westwick

2009 ◽  
Vol 02 (01) ◽  
pp. 93-100 ◽  
Author(s):  
LING ZHU ◽  
TIMON CHENG-YI LIU ◽  
MIN WU ◽  
JIAN-QIN YUAN ◽  
TONG-SHENG CHEN

Photobiomodulation (PBM) is a modulation of monochromatic light or laser irradiation (LI) on biosystems. It is reviewed from the viewpoint of extraocular phototransduction in this paper. It was found that LI can induce extraocular phototransduction, and there may be an exact correspondence relationship of LI at different wavelengths and in different dose zones, and cellular signal transduction pathways. The signal transduction pathways can be classified into two types so that the Gs protein-mediated pathways belong to pathway 1, and the other pathways such as protein kinase Cs -mediated pathways and mitogen-activated protein kinase-mediated pathways belong to pathway 2. Almost all the present pathways found to mediate PBM belong to pathway 2, but there should be a pathway 1-mediated PBM. The previous studies were rather preliminary, and therefore further work should be done.


Sign in / Sign up

Export Citation Format

Share Document