scholarly journals Heat Shock Protein HSP24 Is Involved in the BABA-Induced Resistance to Fungal Pathogen in Postharvest Grapes Underlying an NPR1-Dependent Manner

2021 ◽  
Vol 12 ◽  
Author(s):  
Chunhong Li ◽  
Shifeng Cao ◽  
Kaituo Wang ◽  
Changyi Lei ◽  
Nana Ji ◽  
...  
Keyword(s):  
Heat Shock ◽  
Fungal Pathogen ◽  
Orthologous Gene ◽  
Dependent Manner ◽  
Gene Expressions ◽  
Mobility Shift ◽  
Transcript Levels ◽  
Mold Fungus

Although heat shock proteins (HSPs), a family of ubiquitous molecular chaperones, are well characterized in heat stress-related responses, their function in plant defense remains largely unclear. Here, we report the role of VvHSP24, a class B HSP from Vitis vinifera, in β-aminobutyric acid (BABA)-induced priming defense against the necrotrophic fungus Botrytis cinerea in grapes. Grapes treated with 10 mmol L–1 BABA exhibited transiently increased transcript levels of VvNPR1 and several SA-inducible genes, including PR1, PR2, and PR5. Additionally, phytoalexins accumulated upon inoculation with the gray mold fungus B. cinerea, which coincided with the action of a priming mode implicated in pathogen-driven resistance. Intriguingly, electrophoretic mobility shift (EMSA), yeast two-hybrid (Y2H) and His pull-down assays demonstrated that the nuclear chaperone VvHSP24 cannot modulate the transcript of PR genes but does directly interact with VvNPR1 in vivo or in vitro. Furthermore, we found that VvHSP24 overexpression enhanced the transcript levels of NPR1 and SA-responsive genes (PR1, PR2, and PR5) and increased the resistance of transgenic Arabidopsis thaliana to B. cinerea compared with wildtype Col-0. An opposite trend between CRISPR mutants of AtHSFB1 (the orthologous gene of VvHSP24 in Arabidopsis) and wildtype plants was observed. Hence, our results suggest that VvHSP24 has a potential role in NPR1-dependent plant resistance to fungal pathogen. BABA-induced priming defense in grapes may require posttranslational modification of the chaperone VvHSP24 to activate VvNPR1 transcript, leading to PR gene expressions and resistance phenotypes.

scholarly journals Inhibition of the activation of heat shock factor in vivo and in vitro by flavonoids.

1992 ◽  
Vol 12 (8) ◽  
pp. 3490-3498 ◽  
Author(s):  
N Hosokawa ◽  
K Hirayoshi ◽  
H Kudo ◽  
H Takechi ◽  
A Aoike ◽  
...  
Keyword(s):  
Heat Shock ◽  
Transcriptional Activation ◽  
Heat Shock Factor ◽  
Mobility Shift ◽  
Human Colon Cancer ◽  
Heat Shock Element ◽  
Mrna Accumulation ◽  
Cell Extracts

Transcriptional activation of human heat shock protein (HSP) genes by heat shock or other stresses is regulated by the activation of a heat shock factor (HSF). Activated HSF posttranslationally acquires DNA-binding ability. We previously reported that quercetin and some other flavonoids inhibited the induction of HSPs in HeLa and COLO 320DM cells, derived from a human colon cancer, at the level of mRNA accumulation. In this study, we examined the effects of quercetin on the induction of HSP70 promoter-regulated chloramphenicol acetyltransferase (CAT) activity and on the binding of HSF to the heat shock element (HSE) by a gel mobility shift assay with extracts of COLO 320DM cells. Quercetin inhibited heat-induced CAT activity in COS-7 and COLO 320DM cells which were transfected with plasmids bearing the CAT gene under the control of the promoter region of the human HSP70 gene. Treatment with quercetin inhibited the binding of HSF to the HSE in whole-cell extracts activated in vivo by heat shock and in cytoplasmic extracts activated in vitro by elevated temperature or by urea. The binding of HSF activated in vitro by Nonidet P-40 was not suppressed by the addition of quercetin. The formation of the HSF-HSE complex was not inhibited when quercetin was added only during the binding reaction of HSF to the HSE after in vitro heat activation. Quercetin thus interacts with HSF and inhibits the induction of HSPs after heat shock through inhibition of HSF activation.

scholarly journals In Vitro and in Vivo Immunomodulatory Effects of RDP1258, a Novel Synthetic Peptide

1999 ◽  
Vol 10 (9) ◽  
pp. 1997-2005
Author(s):  
COLM C. MAGEE ◽  
HARUHITO AZUMA ◽  
ANDREAS KNOFLACH ◽  
MARK D. DENTON ◽  
ANIL CHANDRAKER ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heme Oxygenase ◽  
Computer Assisted ◽  
Dependent Manner ◽  
Immunomodulatory Effects ◽  
Heme Oxygenase Activity ◽  
Oxygenase Activity ◽  
Dose Dependent

Abstract. Peptides derived from certain regions of human class I MHC molecules are known to have immunomodulatory effects. In particular, amino acid residues 75-84 of the HLA-B7 and HLA-B2702 molecules have demonstrated allele nonspecific immunosuppression in several animal transplant models. There is evidence that these effects are mediated by binding to intracellular heat shock proteins, including heme oxygenase-1. A new derivative of these peptides, RDP1258, was developed using a novel computer-assisted rational design technique. In vitro, RDP1258 peptide inhibited rat heme oxygenase activity in a dose-dependent manner. Similar to observations made with other in vitro heme oxygenase inhibitors, in vivo administration of RDP1258 peptide to naïve rats resulted in upregulation of splenic heme oxygenase activity. The effects of the peptide on alloimmune responses were then tested. Addition of RDP1258 to rat and human mixed leukocyte reactions inhibited proliferation in a dose-dependent manner. In a rat renal transplantation model, peptide therapy combined with a sub-therapeutic dose of cyclosporin A significantly prolonged allograft survival. These data provide further evidence that modulation of the heat shock protein heme oxygenase by rationally designed peptides affects immune effector functions and may allow the development of novel immunomodulatory strategies in organ transplantation.

Stress causes decrease in vascular relaxation linked with altered phosphorylation of heat shock proteins

2000 ◽  
Vol 279 (2) ◽  
pp. R492-R498 ◽  
Author(s):  
Leslie C. Fuchs ◽  
Ararat D. Giulumian ◽  
Louis Knoepp ◽  
Walter Pipkin ◽  
Mary Dickinson ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Heat Shock ◽  
Vascular Smooth Muscle ◽  
Cyclic Nucleotide ◽  
Cellular Stress ◽  
Dependent Manner ◽  
Vascular Relaxation ◽  
Behavioral Stress

Cyclic nucleotide-dependent vascular relaxation is associated with increases in the phosphorylation of a small heat shock protein (HSP), HSP20. An increase in phosphorylation of another small HSP, HSP27, is associated with impaired cyclic nucleotide-dependent vascular relaxation. Expression of HSPs is altered by exposure to several types of cellular stress in vitro. To determine if behavioral stress in vivo alters vascular expression and phosphorylation of the small HSPs and cyclic nucleotide-dependent vascular relaxation, borderline hypertensive rats were stressed by restraint and exposure to air-jet stress 2 h/day for 10 days or remained in their home cage. Stress impaired relaxation of aorta to forskolin, which activates adenylyl cyclase, and sodium nitroprusside, which activates guanylyl cyclase. This was associated with an increase in the aortic expression and phosphorylation of HSP27, which was localized to the vascular smooth muscle, but a decrease in the amount of phosphorylated (P)-HSP20. To determine if P-HSP27 inhibits phosphorylation of HSP20, P-HSP27 was added to a reaction mixture containing recombinant HSP20 and the catalytic subunit of cAMP-dependent protein kinase. P-HSP27 inhibited phosphorylation of HSP20 in a concentration-dependent manner. These data demonstrate that P-HSP27 can inhibit phosphorylation of HSP20. The increase in P-HSP27 and decrease in P-HSP20 were associated with reduced cyclic nucleotide-dependent vascular smooth muscle relaxation in response to behavioral stress in vivo, an effect similar to that observed previously in response to cellular stress in vitro.

scholarly journals Inhibition of the activation of heat shock factor in vivo and in vitro by flavonoids

1992 ◽  
Vol 12 (8) ◽  
pp. 3490-3498
Author(s):  
N Hosokawa ◽  
K Hirayoshi ◽  
H Kudo ◽  
H Takechi ◽  
A Aoike ◽  
...  
Keyword(s):  
Heat Shock ◽  
Transcriptional Activation ◽  
Heat Shock Factor ◽  
Mobility Shift ◽  
Human Colon Cancer ◽  
Heat Shock Element ◽  
Mrna Accumulation ◽  
Cell Extracts

Transcriptional activation of human heat shock protein (HSP) genes by heat shock or other stresses is regulated by the activation of a heat shock factor (HSF). Activated HSF posttranslationally acquires DNA-binding ability. We previously reported that quercetin and some other flavonoids inhibited the induction of HSPs in HeLa and COLO 320DM cells, derived from a human colon cancer, at the level of mRNA accumulation. In this study, we examined the effects of quercetin on the induction of HSP70 promoter-regulated chloramphenicol acetyltransferase (CAT) activity and on the binding of HSF to the heat shock element (HSE) by a gel mobility shift assay with extracts of COLO 320DM cells. Quercetin inhibited heat-induced CAT activity in COS-7 and COLO 320DM cells which were transfected with plasmids bearing the CAT gene under the control of the promoter region of the human HSP70 gene. Treatment with quercetin inhibited the binding of HSF to the HSE in whole-cell extracts activated in vivo by heat shock and in cytoplasmic extracts activated in vitro by elevated temperature or by urea. The binding of HSF activated in vitro by Nonidet P-40 was not suppressed by the addition of quercetin. The formation of the HSF-HSE complex was not inhibited when quercetin was added only during the binding reaction of HSF to the HSE after in vitro heat activation. Quercetin thus interacts with HSF and inhibits the induction of HSPs after heat shock through inhibition of HSF activation.

scholarly journals Transcriptional regulation of the Zrg17 zinc transporter of the yeast secretory pathway

2011 ◽  
Vol 435 (1) ◽  
pp. 259-266 ◽  
Author(s):  
Yi-Hsuan Wu ◽  
Avery G. Frey ◽  
David J. Eide
Keyword(s):  
Secretory Pathway ◽  
Target Gene ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Mobility Shift ◽  
Protein Levels ◽  
Active Allele ◽  
Responsive Element

The Msc2 and Zrg17 proteins of Saccharomyces cerevisiae are members of the cation diffusion facilitator family of zinc transporters. These proteins form heteromeric complexes that transport zinc into the ER (endoplasmic reticulum). Previous studies suggested that the ZRG17 gene is regulated in response to zinc status by the Zap1 transcription factor. Zap1 activates the expression of many genes in zinc-deficient cells. In the present study, we assessed whether ZRG17 is a direct Zap1 target gene. We showed that ZRG17 mRNA levels were elevated in zinc-limited cells in a Zap1-dependent manner and were also elevated in zinc-replete cells expressing a constitutively active allele of Zap1. Furthermore, Zrg17 protein levels correlated closely with mRNA levels. A candidate Zap1-binding site [ZRE (zinc-responsive element)] in the ZRG17 promoter was required for this induction. Using electrophoretic mobility-shift assays and chromatin immunoprecipitation, we demonstrated that Zap1 binds specifically to the ZRG17 ZRE both in vitro and in vivo. By using a chromosomal ZRG17 mutant with a non-functional ZRE, we found that Zap1 induction of ZRG17 is required for ER function as indicated by elevated ER stress under zinc-limited conditions. Together, these results establish that ZRG17 is a direct Zap1 target gene and its regulation has biological importance in maintaining ER function.

Heat-shock protein 90 augments neuronal nitric oxide synthase activity by enhancing Ca2+/calmodulin binding

2001 ◽  
Vol 355 (2) ◽  
pp. 357-360 ◽  
Author(s):  
Yao SONG ◽  
Jay L. ZWEIER ◽  
Yong XIA
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 90 ◽  
Maximal Activity ◽  
Dependent Manner ◽  
Calmodulin Binding ◽  
Catalytic Function ◽  
Oxide Synthase

Heat-shock protein 90 (hsp90) has been shown to facilitate neuronal NO synthase (nNOS, type 1) activity in vivo. But the direct effect of hsp90 on purified nNOS has not been determined yet. Moreover, the mechanism underlying the action of hsp90 is not known. nNOS activity is primarily initiated and regulated by the binding of Ca2+/calmodulin (CaM). Therefore, we explored whether hsp90 modulates nNOS activity by affecting CaM binding. Recombinant rat nNOS was purified from the stably transfected cells by affinity chromatography. hsp90 increased nNOS activity in a dose-dependent manner with an EC50 of 24.1±6.4nM. In the presence of hsp90, the CaM-nNOS dose-response curve was shifted markedly to the left and the maximal activity was also elevated. Further in vitro protein-binding experiments confirmed that hsp90 increased the binding of CaM to nNOS. Taken together, these data indicate that hsp90 directly augments nNOS catalytic function and that this effect is, at least partially, mediated by CaM-binding enhancement.

Chickpea (Cicer arietinum L.) Lectin Exhibit Inhibition of ACE-I, α-amylase and α-glucosidase Activity

2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  
Keyword(s):  
Biological Effects ◽  
Exchange Chromatography ◽  
Health Concern ◽  
Carbohydrate Binding ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ic50 Values ◽  
Chickpea Lectin

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.

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