scholarly journals The LeATL6-Associated Ubiquitin/Proteasome System May Contribute to Fungal Elicitor-Activated Defense Response via the Jasmonic Acid-Dependent Signaling Pathway in Tomato

2007 ◽  
Vol 20 (1) ◽  
pp. 72-81 ◽  
Author(s):  
Daisuke Hondo ◽  
Shu Hase ◽  
Yoshinori Kanayama ◽  
Nobuyuki Yoshikawa ◽  
Shigehito Takenaka ◽  
...  
Keyword(s):  
Jasmonic Acid ◽  
Signaling Pathway ◽  
Ubiquitin Proteasome System ◽  
Defense Responses ◽  
Cauliflower Mosaic Virus ◽  
35S Promoter ◽  
Pythium Oligandrum ◽  
Wild Tomato ◽  
Ubiquitin Proteasome ◽  
Dependent Signaling Pathway

The expression of LeATL6, an ortholog of Arabidopsis ATL6 that encodes a RING-H2 finger protein, was induced in tomato roots treated with a cell wall protein fraction (CWP) elicitor of the biocontrol agent Pythium oligandrum. The LeATL6 protein was expressed as a fusion protein with a maltose-binding protein (MBP) in Escherichia coli, and it catalyzed the transfer of ubiquitin to the MBP moiety on incubation with ubiquitin, the ubiquitin-activating enzyme E1, and the ubiquitin-conjugating enzyme E2; this indicated that LeATL6 represents ubiquitin ligase E3. LeATL6 expression also was induced by elicitor treatment of jai1-1 mutant tomato cells in which the jasmonic acid (JA)-mediated signaling pathway was impaired; however, JA-dependent expression of the basic PR-6 and TPI-1 genes that encode proteinase inhibitor II and I, respectively, was not induced in elicitor-treated jai1-1 mutants. Furthermore, transient overexpression of LeATL6 under the control of the Cauliflower mosaic virus 35S promoter induced the basic PR6 and TPI-1 expression in wild tomato but not in the jai1-1 mutant. In contrast, LeATL6 overexpression did not activate salicylic acid-responsive acidic PR-1 and PR-2 promoters in wild tomato. These results indicated that elicitor-responsive LeATL6 probably regulates JA-dependent basic PR6 and TPI-1 gene expression in tomato. The LeATL6-associated ubiquitin/proteasome system may contribute to elicitor-activated defense responses via a JA-dependent signaling pathway in plants.

scholarly journals MaRING2: A Positive Regulator of an Abscisic Acid-dependent Response to Cold Stress from Banana Fruit

2015 ◽  
Vol 140 (4) ◽  
pp. 373-382
Author(s):  
Jiao Chen ◽  
De-bao Yuan ◽  
Chao-zheng Wang ◽  
Yi-xing Li ◽  
Fen-fang Li ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
Cold Stress ◽  
Expression Profiles ◽  
Functional Characterization ◽  
Gene Expression Profiles ◽  
Defense Responses ◽  
Cauliflower Mosaic Virus ◽  
35S Promoter ◽  
Banana Fruit ◽  
Positive Regulator

Many reports indicate that an abundance of really interesting new gene (RING) play key roles in regulating defense responses against abiotic and biotic stresses in plants. In this study, the cloning and functional characterization of a RING gene, MaRING2, in banana (Musa acuminata) fruit are reported. MaRING2 belongs to the NEP1-interacting protein (NIP) RING-H2 finger protein family. Gene expression profiles revealed that MaRING2 was cold responsive and induced by abscisic acid (ABA) treatment during cold storage. In this study, the MaRING2 under control of the Cauliflower mosaic virus 35S (CaMV 35S) promoter was transformed to tobacco (Nicotiana benthamiana) using agrobacterium (Agrobacterium tumefaciens)-mediated transformation. The resultant MaRING2-overexpressing transgenic plants (35S:MaRING2) exhibited significantly increased tolerance to low temperatures and were hypersensitive to exogenous ABA in terms of germination and early seedling growth. In addition, overexpression of MaRING2 enhanced the expression of stress-responsive genes under normal (before cold stress) or cold conditions. These results demonstrate the biological role of MaRING2 in conferring cold tolerance. Taken together, these results suggest that MaRING2, a C3H2C3-type RING protein, is a positive regulator of the ABA-dependent stress response.

scholarly journals Enhancer Trapping Identifies TRI, an Arabidopsis Gene Up-Regulated by Pathogen Infection

2004 ◽  
Vol 17 (10) ◽  
pp. 1086-1094 ◽  
Author(s):  
Ingela Fridborg ◽  
Alan Williams ◽  
Aidong Yang ◽  
Stuart MacFarlane ◽  
Katherine Coutts ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Tobacco Rattle Virus ◽  
Defense Responses ◽  
Gus Activity ◽  
Enhancer Trap ◽  
Cauliflower Mosaic Virus ◽  
35S Promoter ◽  
Resistance Response ◽  
Enhancer Element ◽  
Enhancer Trap Line

Enhancer trap Arabidopsis thaliana plants were screened for genes up-regulated by virus infection. The plants carried T-DNA insertions comprising a minimal -60-bp Cauliflower mosaic virus 35S promoter fused to the β-glucuronidase (GUS) reporter gene. Approximately 12,000 plants were assayed for GUS activity before and after rub-inoculation with Tobacco rattle virus (TRV) tagged with the green fluorescent protein (GFP). One plant and its progeny consistently showed upregulation of GUS activity in response to TRV-GFP infection, indicating that a virus-responsive enhancer element was “tagged” by the T-DNA in this line. Other viruses, bacteria, and oomycetes, but not wounding, up-regulated GUS activity in the enhancer trap line, indicating that the response was not specific to TRV-GFP infection. A pathogen-inducible, alternatively spliced gene was identified, which we have termed TRI for TRV-induced gene. A pathogen-responsive element was localized to a 1.1-kb region upstream of the T-DNA insertion, and two different cis-acting elements, both implicated in defense responses, were found in the sequence upstream of TRI. Sequence analyses revealed that TRI is similar to ACRE169, a gene that is up-regulated in Cf-9-expressing tobacco when treated with Avr-9, the Cladosporium fulvum elicitor of the Cf-9 resistance response.

scholarly journals GhPLP2 Positively Regulates Cotton Resistance to Verticillium Wilt by Modulating Fatty Acid Accumulation and Jasmonic Acid Signaling Pathway

2021 ◽  
Vol 12 ◽  
Author(s):  
Yutao Zhu ◽  
Xiaoqian Hu ◽  
Ping Wang ◽  
Linying Gao ◽  
Yakun Pei ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Linoleic Acid ◽  
Jasmonic Acid ◽  
Signaling Pathway ◽  
Linolenic Acid ◽  
Membrane Lipids ◽  
Defense Responses ◽  
Vital Role ◽  
Defensive Responses ◽  
Cotton Plants

Patatin-like proteins (PLPs) have non-specific lipid acyl hydrolysis (LAH) activity, which can hydrolyze membrane lipids into fatty acids and lysophospholipids. The vital role of PLPs in plant growth and abiotic stress has been well documented. However, the function of PLPs in plant defense responses against pathogens is still poorly understood. Here, we isolated and identified a novel cotton (Gossypium hirsutum) PLP gene GhPLP2. The expression of GhPLP2 was induced upon treatment with Verticillium dahliae, the signaling molecules jasmonic acid (JA) and ethylene (ETH) in cotton plants. Subcellular localization revealed that GhPLP2 was localized to the plasma membrane. GhPLP2-silenced cotton plants were more susceptible to infection by V. dahliae, while the overexpression of GhPLP2 in Arabidopsis enhanced its resistance to V. dahliae, which was apparent as mild symptoms, and a decrease in the disease index and fungal biomass. The hypersensitive response, deposition of callose, and H2O2 accumulation triggered by V. dahliae elicitor were reduced in GhPLP2-silenced cotton plants. The overexpression of GhPLP2 in Arabidopsis resulted in the accumulation of linoleic acid (LA, 18:2) and α-linolenic acid (ALA, 18:3) and facilitated the biosynthesis of JA and JA-mediated defensive responses. GhPLP2 silencing in cotton plants consistently reduced the accumulation of linoleic acid (LA, 18:2) and α-linolenic acid (ALA, 18:3) and suppressed the biosynthesis of JA and the defensive responses mediated by JA. These results indicate that GhPLP2 is involved in the resistance of cotton to V. dahliae by maintaining fatty acid metabolism pools for JA biosynthesis and activating the JA signaling pathway.

scholarly journals TcpC inhibits toll-like receptor signaling pathway by serving as an E3 ubiquitin ligase that promotes degradation of myeloid differentiation factor 88

2021 ◽  
Vol 17 (3) ◽  
pp. e1009481
Author(s):  
Jia-qi Fang ◽  
Qian Ou ◽  
Jun Pan ◽  
Jie Fang ◽  
Da-yong Zhang ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Ubiquitin Ligase ◽  
Bacterial Pathogens ◽  
E3 Ubiquitin Ligase ◽  
Ubiquitin Proteasome System ◽  
Mrna Levels ◽  
Tlr Signaling ◽  
Protein Levels ◽  
Ubiquitin Proteasome ◽  
Myeloid Differentiation Factor

TcpC is a virulence factor of uropathogenic E. coli (UPEC). It was found that TIR domain of TcpC impedes TLR signaling by direct association with MyD88. It has been a long-standing question whether bacterial pathogens have evolved a mechanism to manipulate MyD88 degradation by ubiquitin-proteasome pathway. Here, we show that TcpC is a MyD88-targeted E3 ubiquitin ligase. Kidney macrophages from mice with pyelonephritis induced by TcpC-secreting UPEC showed significantly decreased MyD88 protein levels. Recombinant TcpC (rTcpC) dose-dependently inhibited protein but not mRNA levels of MyD88 in macrophages. Moreover, rTcpC significantly promoted MyD88 ubiquitination and accumulation in proteasomes in macrophages. Cys12 and Trp106 in TcpC are crucial amino acids in maintaining its E3 activity. Therefore, TcpC blocks TLR signaling pathway by degradation of MyD88 through ubiquitin-proteasome system. Our findings provide not only a novel biochemical mechanism underlying TcpC-medicated immune evasion, but also the first example that bacterial pathogens inhibit MyD88-mediated signaling pathway by virulence factors that function as E3 ubiquitin ligase.

scholarly journals Proteasome homeostasis is essential for a robust cauliflower mosaic virus infection

2021 ◽  
Author(s):  
Aayushi Shukla ◽  
Suayib Ustun ◽  
Anders Hafrén
Keyword(s):  
Mosaic Virus ◽  
Viral Infections ◽  
Plant Immunity ◽  
Ubiquitin Proteasome System ◽  
Cauliflower Mosaic Virus ◽  
Fine Tuning ◽  
Cellular Processes ◽  
Ubiquitin Proteasome ◽  
Specific Virus ◽  
And Shifts

SummaryThe ubiquitin-proteasome system (UPS) is essential for the maintenance and shifts in protein homeostasis, and thereby forms a founding pillar in virtually all cellular processes including plant immunity and viral infections. According to its importance in fine-tuning the complex plant immune response, proteasomal defects result in divergent outcomes including both resistance and susceptibility phenotypes in response to viruses. The final outcome will largely depend on the specific virus and its specific co-adaptation with the UPS as well as the immune system. Here, we show that cauliflower mosaic virus (CaMV) relies on the proteasome for robust infection. The proteasome system is induced during infection via SA and supports systemic accumulation of the virus as well as plant growth performance during infection. This establishes the UPS as a win-win pathway for the plant and the virus, and together with our demonstration of a proteasome-suppressing viral effector, the intimacy between the proteasome and CaMV is fortified.

scholarly journals Senescence associated protein degradation

2017 ◽  
Author(s):  
Gerardo Ferbeyre
Keyword(s):  
Process Control ◽  
Protein Degradation ◽  
Signaling Pathway ◽  
Old Age ◽  
Ubiquitin Proteasome System ◽  
General Role ◽  
Cellular Processes ◽  
Ubiquitin Proteasome ◽  
Kinase Signaling Pathway ◽  
Map Kinase Signaling Pathway

AbstractSenescent cells accumulate with age and contribute to pathologies associated to old age. The senescent program can be induced by pro-cancer stimuli or is developmentally controlled. In cells forced to senesce by expression of oncogenes or short telomeres, aberrant activation of the ERK/MAP kinase signaling pathway leads to selective protein degradation by the ubiquitin proteasome system. The proteins affected by this process control key cellular processes known to be defective in senescent cells. We discuss the evidence supporting a general role for senescence associated protein degradation for organismal aging.

scholarly journals Yi–Qi–Jian–Pi–Xiao–Yu–Xie–Zhuo Formula Improves Muscle Atrophy via Modulating the IGF-1/PI3K/Akt Signaling Pathway in 5/6 Nephrectomized Rats

2021 ◽  
Vol 12 ◽  
Author(s):  
Hong Xia ◽  
Bingbing Zhang ◽  
Dan Yang ◽  
Chengyue Zhu ◽  
Jiudan Zhang ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Muscle Atrophy ◽  
Muscle Wasting ◽  
Body Weight Loss ◽  
Ubiquitin Proteasome System ◽  
Akt Signaling ◽  
Akt Signaling Pathway ◽  
Good Efficiency ◽  
Fiber Size ◽  
Ubiquitin Proteasome

The Yi–Qi–Jian–Pi–Xiao–Yu–Xie–Zhuo (YQJPXYXZ) formula has been used for treating chronic kidney disease (CKD) for many years with good efficiency based on the cumulative empirical experience of previous practitioners. Impairment of the IGF-1/PI3K/Akt signaling pathway plays an important role in mediating muscle wasting. This study aimed to observe effects of the YQJPXYXZ formula on muscle atrophy in CKD rats and investigate its possible mechanism on regulation of the IGF-1/PI3K/Akt signaling pathway. The 5/6 nephrectomized rats were randomly allocated into 3 groups: the CKD group, the KT (compound α-ketoacid tablets) group, and the YQJPXYXZ group. Besides, sham-operated rats were included as the sham group. All rats were treated for 12 weeks. Results showed that administration of the YQJPXYXZ formula prevented body weight loss and muscle fiber size decrease. Moreover, the YQJPXYXZ formula increased the IGF-1 level of serum and skeletal muscle in CKD rats and enhanced the phosphorylation level of Akt. Furthermore, the YQJPXYXZ formula decreased the Atrogin1 and MuRF1 mRNA and MuRF1 proteins. In conclusion, our data demonstrated that the YQJPXYXZ formula improves muscle wasting in CKD rats, which might be associated with the modulation of the IGF-1/PI3K/Akt signaling pathway and inhibition of the ubiquitin–proteasome system (UPS).

The ubiquitin–proteasome system and skeletal muscle wasting

2005 ◽  
Vol 41 ◽  
pp. 173-186 ◽  
Author(s):  
Didier Attaix ◽  
Sophie Ventadour ◽  
Audrey Codran ◽  
Daniel Béchet ◽  
Daniel Taillandier ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Wasting ◽  
Proteolytic Enzymes ◽  
Cathepsin L ◽  
Ubiquitin Proteasome System ◽  
Complete Breakdown ◽  
Skeletal Muscle Proteins ◽  
Ubiquitin Proteasome ◽  
Tripeptidyl Peptidase Ii ◽  
F Box Protein

The ubiquitin–proteasome system (UPS) is believed to degrade the major contractile skeletal muscle proteins and plays a major role in muscle wasting. Different and multiple events in the ubiquitination, deubiquitination and proteolytic machineries are responsible for the activation of the system and subsequent muscle wasting. However, other proteolytic enzymes act upstream (possibly m-calpain, cathepsin L, and/or caspase 3) and downstream (tripeptidyl-peptidase II and aminopeptidases) of the UPS, for the complete breakdown of the myofibrillar proteins into free amino acids. Recent studies have identified a few critical proteins that seem necessary for muscle wasting {i.e. the MAFbx (muscle atrophy F-box protein, also called atrogin-1) and MuRF-1 [muscle-specific RING (really interesting new gene) finger 1] ubiquitin–protein ligases}. The characterization of their signalling pathways is leading to new pharmacological approaches that can be useful to block or partially prevent muscle wasting in human patients.

Sign in / Sign up

Export Citation Format

Share Document