scholarly journals eIF2α Phosphorylation by GCN2 Is Induced in the Presence of Chitin and Plays an Important Role in Plant Defense against B. cinerea Infection

2020 ◽  
Vol 21 (19) ◽  
pp. 7335 ◽  
Author(s):  
Marta Berrocal-Lobo ◽  
René Toribio ◽  
M. Mar Castellano
Keyword(s):  
Plant Defense ◽  
Translational Regulation ◽  
De Novo ◽  
Specific Response ◽  
Abiotic And Biotic Stresses ◽  
Biotic Stresses ◽  
Eif2α Phosphorylation ◽  
Molecular Pattern ◽  
De Novo Protein Synthesis ◽  
Global Inhibition

Translation plays an important role in plant adaptation to different abiotic and biotic stresses; however, the mechanisms involved in translational regulation during each specific response and their effect in translation are poorly understood in plants. In this work, we show that GCN2 promotes eIF2α phosphorylation upon contact with Botrytis cinerea spores, and that this phosphorylation is required for the proper establishment of plant defense against the fungus. In fact, independent gcn2 mutants display an enhanced susceptibility to B. cinerea infection, which is highlighted by an increased cell death and reduced expression of ethylene- and jasmonic-related genes in the gcn2 mutants. eIF2α phosphorylation is not only triggered in the presence of the fungus, but interestingly, is also achieved in the sole presence of the microbe-associated molecular pattern (MAMP) chitin. Moreover, analysis of de novo protein synthesis by 35SMet–35SCys incorporation indicates that chitin treatment promotes a global inhibition of translation. Taken together, these results suggest that eIF2α phosphorylation by GCN2 is promoted in the presence of chitin and plays an important role in plant defense against B. cinerea infection.

scholarly journals Translation from the Ribosome to the Clinic: Implication in Neurological Disorders and New Perspectives from Recent Advances

Biomolecules ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 680 ◽  
Author(s):  
Hui ◽  
Chen ◽  
Endo ◽  
Tanaka
Keyword(s):  
Neurological Disorders ◽  
Translational Regulation ◽  
De Novo ◽  
Ribosome Profiling ◽  
The Right ◽  
The Brain ◽  
De Novo Protein Synthesis ◽  
Pathogenic Process ◽  
Liquid Liquid Phase Separation ◽  
Better Than

De novo protein synthesis by the ribosome and its multitude of co-factors must occur in a tightly regulated manner to ensure that the correct proteins are produced accurately at the right time and, in some cases, also in the proper location. With novel techniques such as ribosome profiling and cryogenic electron microscopy, our understanding of this basic biological process is better than ever and continues to grow. Concurrently, increasing attention is focused on how translational regulation in the brain may be disrupted during the progression of various neurological disorders. In fact, translational dysregulation is now recognized as the de facto pathogenic cause for some disorders. Novel mechanisms including ribosome stalling, ribosome-associated quality control, and liquid-liquid phase separation are closely linked to translational regulation, and may thus be involved in the pathogenic process. The relationships between translational dysregulation and neurological disorders, as well as the ways through which we may be able to reverse those detrimental effects, will be examined in this review.

scholarly journals GADD34-mediated dephosphorylation of eIF2α facilitates pseudorabies virus replication by maintaining de novo protein synthesis

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Ting Zhu ◽  
Xueli Jiang ◽  
Hangkuo Xin ◽  
Xiaohui Zheng ◽  
Xiaonuan Xue ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Protein Kinase ◽  
Pseudorabies Virus ◽  
De Novo ◽  
Initiation Factor ◽  
Protein Kinase R ◽  
Eif2α Phosphorylation ◽  
Phosphorylation Level ◽  
Global Protein Synthesis ◽  
De Novo Protein Synthesis

AbstractViruses have evolved multiple strategies to manipulate their host’s translational machinery for the synthesis of viral proteins. A common viral target is the alpha subunit of eukaryotic initiation factor 2 (eIF2α). In this study, we show that global protein synthesis was increased but the eIF2α phosphorylation level was markedly decreased in porcine kidney 15 (PK15) cells infected with pseudorabies virus (PRV), a swine herpesvirus. An increase in the eIF2α phosphorylation level by salubrinal treatment or transfection of constructs expressing wild-type eIF2α or an eIF2α phosphomimetic [eIF2α(S51D)] attenuated global protein synthesis and suppressed PRV replication. To explore the mechanism involved in the inhibition of eIF2α phosphorylation during PRV infection, we examined the phosphorylation status of protein kinase R-like endoplasmic reticulum kinase (PERK) and double-stranded RNA-dependent protein kinase R (PKR), two kinases that regulate eIF2α phosphorylation during infection with numerous viruses. We found that the level of neither phosphorylated (p)-PERK nor p-PKR was altered in PRV-infected cells or the lungs of infected mice. However, the expression of growth arrest and DNA damage-inducible protein 34 (GADD34), which promotes eIF2α dephosphorylation by recruiting protein phosphatase 1 (PP1), was significantly induced both in vivo and in vitro. Knockdown of GADD34 and inhibition of PP1 activity by okadaic acid treatment led to increased eIF2α phosphorylation but significantly suppressed global protein synthesis and inhibited PRV replication. Collectively, these results demonstrated that PRV induces GADD34 expression to promote eIF2α dephosphorylation, thereby maintaining de novo protein synthesis and facilitating viral replication.

scholarly journals Production of constitutive and induced secondary metabolites is coordinated with growth and storage in Norway spruce saplings

2020 ◽  
Vol 40 (7) ◽  
pp. 928-942 ◽  
Author(s):  
Jianbei Huang ◽  
Alexander Rücker ◽  
Axel Schmidt ◽  
Gerd Gleixner ◽  
Jonathan Gershenzon ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Norway Spruce ◽  
De Novo ◽  
Soluble Sugars ◽  
Carbon Limitation ◽  
Complete Darkness ◽  
Abiotic And Biotic Stresses ◽  
Biotic Stresses ◽  
Trade Offs ◽  
And Storage

Abstract A mechanistic understanding of how trees balance the trade-offs between growth, storage and defense is limited but crucial for predicting tree responses to abiotic and biotic stresses. Here we investigated how trees allocate storage of non-structural carbohydrates (NSC) to growth and constitutive and induced secondary metabolites (SM). We exposed Norway spruce (Picea abies) saplings to 5 weeks of complete darkness to induce light and/or carbon limitation and then applied methyl jasmonate (MeJA) to simulate biotic attack. We measured changes in biomass, NSC (sum of soluble sugars and starches), and constitutive and induced SM (sum of phenolic compounds and terpenoids) in current-year developing and previous-year mature needles and branches, as well as volatiles emitted from the canopy. Under darkness, NSC storage was preferentially used for constitutive biosynthesis of monoterpenes rather than biosynthesis of stilbenes and growth of developing organs, while SM stored in mature organs cannot be remobilized and recycled. Furthermore, MeJA-induced production of SM was constrained by low NSC availability in developing organs but not in mature organs grown in the dark. Emissions of volatiles were suppressed in the dark but after 1 h of re-illumination, emissions of both constitutive and induced monoterpene hydrocarbons recovered rapidly, whereas emissions of linalool and sesquiterpene produced via de novo synthesis did not recover. Our results highlight that light and/or carbon limitation may constrain constitutive and JA-induced biosynthesis of SM in coordination with growth, NSC storage and mobilization.

Identification of Plant Protein Kinases in Response to Abiotic and Biotic Stresses Using SuperSAGE

2011 ◽  
Vol 12 (7) ◽  
pp. 643-656 ◽  
Author(s):  
Ederson Akio Kido ◽  
Pedranne Kelle de Araujo Barbosa ◽  
Jose Ribamar Costa Ferreira Neto ◽  
Valesca Pandolfi ◽  
Laureen Michelle Houllou-Kido ◽  
...  
Keyword(s):  
Protein Kinases ◽  
Plant Protein ◽  
Abiotic And Biotic Stresses ◽  
Biotic Stresses

scholarly journals Recent Development on Plant Aldehyde Dehydrogenase Enzymes and Their Functions in Plant Development and Stress Signaling

Genes ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 51
Author(s):  
Adesola J. Tola ◽  
Amal Jaballi ◽  
Hugo Germain ◽  
Tagnon D. Missihoun
Keyword(s):  
Plant Development ◽  
Critical Analysis ◽  
Current Knowledge ◽  
Stress Signaling ◽  
Oxygen Species ◽  
Abiotic And Biotic Stresses ◽  
Aldehyde Dehydrogenases ◽  
Biotic Stresses ◽  
Wide Range ◽  
Excessive Accumulation

Abiotic and biotic stresses induce the formation of reactive oxygen species (ROS), which subsequently causes the excessive accumulation of aldehydes in cells. Stress-derived aldehydes are commonly designated as reactive electrophile species (RES) as a result of the presence of an electrophilic α, β-unsaturated carbonyl group. Aldehyde dehydrogenases (ALDHs) are NAD(P)+-dependent enzymes that metabolize a wide range of endogenous and exogenous aliphatic and aromatic aldehyde molecules by oxidizing them to their corresponding carboxylic acids. The ALDH enzymes are found in nearly all organisms, and plants contain fourteen ALDH protein families. In this review, we performed a critical analysis of the research reports over the last decade on plant ALDHs. Newly discovered roles for these enzymes in metabolism, signaling and development have been highlighted and discussed. We concluded with suggestions for future investigations to exploit the potential of these enzymes in biotechnology and to improve our current knowledge about these enzymes in gene signaling and plant development.

scholarly journals Viral Gene Expression Patterns in Human Herpesvirus 6B-Infected T Cells

2002 ◽  
Vol 76 (15) ◽  
pp. 7578-7586 ◽  
Author(s):  
Bodil Øster ◽  
Per Höllsberg
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
Protein Synthesis ◽  
De Novo ◽  
Expression Patterns ◽  
Human Herpesvirus ◽  
Viral Gene Expression ◽  
Polymerase Activity ◽  
Viral Gene ◽  
De Novo Protein Synthesis

ABSTRACT Herpesvirus gene expression is divided into immediate-early (IE) or α genes, early (E) or β genes, and late (L) or γ genes on the basis of temporal expression and dependency on other gene products. By using real-time PCR, we have investigated the expression of 35 human herpesvirus 6B (HHV-6B) genes in T cells infected by strain PL-1. Kinetic analysis and dependency on de novo protein synthesis and viral DNA polymerase activity suggest that the HHV-6B genes segregate into six separate kinetic groups. The genes expressed early (groups I and II) and late (groups V and VI) corresponded well with IE and L genes, whereas the intermediate groups III and IV contained E and L genes. Although HHV-6B has characteristics similar to those of other roseoloviruses in its overall gene regulation, we detected three B-variant-specific IE genes. Moreover, genes that were independent of de novo protein synthesis clustered in an area of the viral genome that has the lowest identity to the HHV-6A variant. The organization of IE genes in an area of the genome that differs from that of HHV-6A underscores the distinct differences between HHV-6B and HHV-6A and may provide a basis for further molecular and immunological analyses to elucidate their different biological behaviors.

De novo protein synthesis in relation to ammonia and proline accumulation in water stressed white clover

2004 ◽  
Vol 31 (8) ◽  
pp. 847 ◽  
Author(s):  
Tae-Hwan Kim ◽  
Bok-Rye Lee ◽  
Woo-Jin Jung ◽  
Kil-Yong Kim ◽  
Jean-Christophe Avice ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Water Deficit ◽  
White Clover ◽  
De Novo ◽  
Proline Accumulation ◽  
Leaf Water ◽  
Total N ◽  
Water Parameters ◽  
Leaves And Roots ◽  
De Novo Protein Synthesis

The kinetics of protein incorporation from newly-absorbed nitrogen (N, de novo protein synthesis) was estimated by 15N tracing in 18-week-old white clover plants (Trifolium repens L. cv. Regal) during 7 d of water-deficit treatment. The physiological relationship between kinetics and accumulation of proline and ammonia in response to the change in leaf-water parameters was also assessed. All leaf-water parameters measured decreased gradually under water deficit. Leaf and root dry mass was not significantly affected during the first 3 d when decreases in leaf-water parameters were substantial. However, metabolic parameters such as total N, proline and ammonia were significantly affected within 1 d of commencement of water-deficit treatment. Water-deficit treatment significantly increased the proline and NH3–NH4+ concentrations in both leaves and roots. There was a marked reduction in the amount of N incorporated into the protein fraction from the newly absorbed N (NANP) in water-deficit stressed plants, particularly in leaf tissue. This reduction in NANP was strongly associated with an increased concentration of NH3–NH4+ in roots (P≤0.05) and proline (P≤0.01) in leaves and roots. These results suggest that proline accumulation may be a sensitive biochemical indicator of plant water status and of the dynamics of de novo protein synthesis in response to stress severity.

Sign in / Sign up

Export Citation Format

Share Document