Overexpression of DUF538 from Wild Arachis Enhances Plant Resistance to Meloidogyne spp.

DUF538 proteins belong to a large group of uncharacterized protein families sharing the highly conserved Domain of Unknown Function (DUF). Attention has been given to DUF538 domain-containing proteins due to changes in their gene expression behavior and protein abundance during plant development and responses to stress. Putative roles attributed to DUF538 in plants under abiotic and biotic constraints include involvement in cell redox balance, chlorophyll breakdown and pectin degradation. Our previous transcriptome studies suggested that DUF538 is also involved in the resistance responses of wild Arachis species against the highly hazardous root-knot nematodes (RKNs). To clarify the role of the AsDUF538 gene from the wild peanut relative Arachis stenosperma in this interaction, we analyzed the effect of its overexpression on RKN infection in peanut and soybean hairy roots and Arabidopsis transgenic plants. AsDUF538 overexpression significantly reduced the infection in all three heterologous plant systems against their respective RKN counterparts. The distribution of AsDUF538 transcripts in RKN-infected Arachis roots and the effects of AsDUF538 overexpression on hormonal pathways and redox system in transgenic Arabidopsis were also evaluated. This is the first time that a DUF538 gene is functionally validated in transgenic plants and the earliest report on its role in plant defense against RKNs.

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YhcB (DUF1043), a novel cell division protein conserved across gamma-proteobacteria

10.1101/2020.12.31.425005 ◽

2021 ◽

Author(s):

Jitender Mehla ◽

George Liechti ◽

Randy M Morgenstern ◽

J. Harry Caufield ◽

Ali Hosseinnia ◽

...

Keyword(s):

Cell Division ◽

Point Mutations ◽

Coiled Coil ◽

Alpha Helix ◽

Uncharacterized Protein ◽

Knock Out ◽

Essential Protein ◽

Gamma Proteobacteria ◽

Domain Of Unknown Function ◽

Intersubunit Interactions

YhcB, an uncharacterized protein conserved across gamma-proteobacteria, is composed predominantly of a single Domain of Unknown Function (DUF 1043) with an N-terminal transmembrane alpha-helix. Here, we show that E. coli YhcB is a conditionally essential protein that interacts with the proteins of the cell divisome (e.g., FtsI, FtsQ) and elongasome (e.g., RodZ, RodA). We found 7 interactions of YhcB that are conserved in Yersinia pestis and/or Vibrio cholerae. Furthermore, we identified several point mutations that abolished interactions of YhcB with FtsI and RodZ. The YhcB knock-out strain does not grow at 45C and is hypersensitive to cell-wall acting antibiotics even in stationary phase. The deletion of yhcB leads to filamentation, abnormal FtsZ ring formation, and aberrant septa development. The 2.8 angstrom crystal structure for the cytosolic domain from Haemophilus ducreyi YhcB shows a unique tetrameric alpha-helical coiled-coil structure that combines parallel and anti-parallel coiled-coil intersubunit interactions. This structure is likely to organize interprotein oligomeric interactions on the inner surface of the cytoplasmic membrane, possibly involved in regulation of cell division and/or envelope biogenesis/integrity in proteobacteria. In summary, YhcB is a conserved and conditionally essential protein that is predicted to play a role in cell division and consequently or in addition affects envelope biogenesis.

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Transgenic lines of Begonia maculata generated by ectopic expression of PttKN1

Biologia ◽

10.2478/s11756-011-0008-3 ◽

2011 ◽

Vol 66 (2) ◽

Cited By ~ 1

Author(s):

Quan-le Xu ◽

Jiang-ling Dong ◽

Nan Gao ◽

Mei-yu Ruan ◽

Hai-yan Jia ◽

...

Keyword(s):

Transgenic Plants ◽

Ectopic Expression ◽

Class I ◽

Wild Type Plant ◽

Wild Type ◽

Knox Gene ◽

Knox Genes ◽

Pttkn1 Gene ◽

Transgenic Lines ◽

First Time

AbstractKNOX (KNOTTED1-like homeobox) genes encode homeodomain-containing transcription factors which play crucial roles in meristem maintenance and proper patterning of organ initiation. PttKN1 gene, isolated from the vascular cambium of hybrid aspen (Populus tremula × P. tremuloides), is a member of class I KNOX gene family. In order to understand the roles of PttKN1 gene in meristem activity and morphogenesis as well as to explore the possibility to generate novel ornamental lines via its ectopic expression, it was introduced into the genome of Begonia maculata Raddi by Agrobacterium tumefasciens-mediated gene transformation here. Four types of transgenic plants were observed, namely coral-like (CL) type, ectopic foliole (EF) type, phyllotaxy-irregular (IP) type and cup-shaped (CS) type, which were remarkably different from corresponding wild type and were not also observed in the regenerated plantlets of wild type plant. Among these four types of transgenic plants, the phenotype of coral-like was observed for the first time in the transformants ectopically expressed KNOX genes. The observation of scanning electron microscope (SEM) showed ectopic meristems on the adaxial leaf surface of the transformants. Interestingly, the plantlets with ectopic foliole could generate new ectopic folioles from the original ectopic folioles again, and the plants regenerated from the EF-type transformants could also maintain the original morphology. The same specific RT-PCR band of the four types of transgenic plantlets showed that PttKN1 was ectopically expressed. All these data demonstrated that the ectopic expression of PttKN1 caused a series of alterations in morphology which provided possibilities producing novel ornamental lines and that PttKN1 played important roles in meristem initiation, maintenance and organogenesis events as other class I KNOX genes.

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Optimized RNA-Silencing Strategies for Rice Ragged Stunt Virus Resistance in Rice

Plants ◽

10.3390/plants10102008 ◽

2021 ◽

Vol 10 (10) ◽

pp. 2008

Author(s):

Severine Lacombe ◽

Martine Bangratz ◽

Hoang Anh Ta ◽

Thanh Duc Nguyen ◽

Pascal Gantet ◽

...

Keyword(s):

Transgenic Plants ◽

Inverted Repeat ◽

Rna Silencing ◽

Durable Resistance ◽

Genetic Resistance ◽

Environmentally Friendly ◽

Rice Plants ◽

First Time ◽

Inverted Repeat Construct ◽

Rice Ragged Stunt Virus

Rice ragged stunt virus (RRSV) is one of the most damaging viruses of the rice culture area in south and far-eastern Asia. To date, no genetic resistance has been identified and only expensive and non-environmentally friendly chemical treatments are deployed to fight this important disease. Non-chemical approaches based on RNA-silencing have been developed as resistance strategies against viruses. Here, we optimized classical miRNA and siRNA-based strategies to obtain efficient and durable resistance to RRSV. miRNA-based strategies are involved in producing artificial miRNA (amiR) targeting viral genomes in plants. Classically, only one amiR is produced from a single construct. We demonstrated for the first time that two amiRs targeting conserved regions of RRSV genomes could be transgenically produced in Nicotiana benthamiana and in rice for a single precursor. Transgenic rice plants producing either one or two amiR were produced. Despite efficient amiR accumulations, miRNA-based strategies with single or double amiRs failed to achieve efficient RRSV resistance in transformed rice plants. This suggests that this strategy may not be adapted to RRSV, which could rapidly evolve to counteract them. Another RNA-silencing-based method for viral resistance concerns producing several viral siRNAs targeting a viral fragment. These viral siRNAs are produced from an inverted repeat construct carrying the targeted viral fragment. Here, we optimized the inverted repeat construct using a chimeric fragment carrying conserved sequences of three different RRSV genes instead of one. Of the three selected homozygous transgenic plants, one failed to accumulate the expected siRNA. The two other ones accumulated siRNAs from either one or three fragments. A strong reduction of RRSV symptoms was observed only in transgenic plants expressing siRNAs. We consequently demonstrated, for the first time, an efficient and environmentally friendly resistance to RRSV in rice based on the siRNA-mediated strategy.

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Identification and Function of Apicoplast Glutaredoxins in Neospora caninum

International Journal of Molecular Sciences ◽

10.3390/ijms222111946 ◽

2021 ◽

Vol 22 (21) ◽

pp. 11946

Author(s):

Xingju Song ◽

Xu Yang ◽

Zhu Ying ◽

Heng Zhang ◽

Jing Liu ◽

...

Keyword(s):

Neospora Caninum ◽

Tricarboxylic Acid Cycle ◽

Single Gene ◽

Redox System ◽

Protein Translation ◽

Redox Balance ◽

Reproductive Capacity ◽

Double Knockout ◽

Thiol Redox ◽

Amino Acid Mutations

Glutaredoxins (GRXs), important components of the intracellular thiol redox system, are involved in multiple cellular processes. In a previous study, we identified five GRXs in the apicomplexan parasite, Neospora caninum. In the present study, we confirmed that the GRXs S14 and C5 are located in the apicoplast, which suggests unique functions for these proteins. Although single-gene deficiency did not affect the growth of parasites, a double knockout (Δgrx S14Δgrx C5) significantly reduced their reproductive capacity. However, there were no significant changes in redox indices (GSH/GSSG ratio, reactive oxygen species and hydroxyl radical levels) in double-knockout parasites, indicating that grx S14 and grx C5 are not essential for maintaining the redox balance in parasite cells. Key amino acid mutations confirmed that the Cys203 of grx S14 and Cys253/256 of grx C5 are important for parasite growth. Based on comparative proteomics, 79 proteins were significantly downregulated in double-knockout parasites, including proteins mainly involved in the electron transport chain, the tricarboxylic acid cycle and protein translation. Collectively, GRX S14 and GRX C5 coordinate the growth of parasites. However, considering their special localization, the unique functions of GRX S14 and GRX C5 need to be further studied.

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Melatonin inhibits peroxide production in plant mitochondria

Доклады Академии наук ◽

10.31857/s0869-56524892205-208 ◽

2019 ◽

Vol 489 (2) ◽

pp. 205-208

Author(s):

P. A. Butsanets ◽

A. S. Baik ◽

A. G. Shugaev ◽

Vl. V. Kuznetsov

Keyword(s):

Plant Mitochondria ◽

Respiratory Control ◽

Redox Balance ◽

Inhibitory Effect ◽

Control Coefficient ◽

Succinate Oxidation ◽

Significant Inhibitory Effect ◽

Pea Seedlings ◽

Antioxidant Function ◽

First Time

The effect of melatonin on respiration and production (release) of hydrogen peroxide during succinate oxidation in mitochondria isolated from lupine cotyledons and epicotyls of pea seedlings was studied. It has been shown for the first time that melatonin (10-7-10-3 M) had a significant inhibitory effect on the production of peroxide by plant mitochondria, which was characterized by concentration dependence and species specificity. At the same time, melatonin (at a concentration of up to 100 microns) had virtually no effect on mitochondrial respiration rate and respiratory control coefficient. The results confirm the antioxidant function of melatonin and indicate that it is involved in the regulation of ROS levels and maintenance of redox balance in plant mitochondria.

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New Reduction-Oxidation Indices Applied to Mixtures in the Impact on Seasonal and Circadian Rhythm Studies of The Essential Oil From Leaves of Piper Gaudichaudianum Kunth (Piperaceae) – A Folk Medicine and Ritualistic Plant

10.21203/rs.3.rs-730506/v1 ◽

2021 ◽

Author(s):

Ygor Jessé Ramos ◽

Claudete da Costa-Oliveira ◽

Irene Candido-Fonseca ◽

George Azevedo de Queiroz ◽

Elsie Franklin Guimarães ◽

...

Keyword(s):

Circadian Rhythm ◽

Chemical Composition ◽

Folk Medicine ◽

Weighted Average ◽

Redox Balance ◽

Phenological Stages ◽

Composition Variation ◽

Piper Gaudichaudianum ◽

The Impact ◽

First Time

Abstract Piper gaudichaudianum Kunth (Piperaceae) is widely used in Brazil as medicinal and ritualistic. In this study, chemophenetic patterns were evaluated based on leaves’ essential oils (EOs) chemical composition. Several collections were performed to accomplish circadian rhythm and seasonal studies. Besides, a predictive methodology was developed and submitted to Proof of Concept (PoC) to determine the metabolism pattern and evaluate the reduction-oxidation of complex mixtures: Weighted Average Redox Standard (SRO) and General Mixture Redox Index (GMOR). Fresh leaves EOs obtained by hydrodistillation were analyzed by GC-MS and GC-FID. The main identified compounds were sesquiterpenes. Nineteen terpene skeletons were registered. There was chemical composition variation at different phenological stages. EOs varied more between day and night than seasonally. Nine chemotypes are proposed based on our results and those from literature. SRO and GMRO analyzes highlighted a possible redox balance throughout day and night. Compounds per carbon skeleton diversification in EOs are matched by an increase in compounds SRO. We also report for the first time high chemical phenotype plasticity based on EOs analysis and its implications for P. gaudichaudianum chemophenetics, chemosystematics and ecology.

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Trypanothione metabolism as Drug Target for Trypanosomatids.

Current Pharmaceutical Design ◽

10.2174/1381612826666201211115329 ◽

2020 ◽

Vol 26 ◽

Author(s):

María Dolores Piñeyro ◽

Diego G Arias ◽

Adriana Parodi-Talice ◽

Sergio A Guerrero ◽

Carlos Robello

Keyword(s):

Methionine Sulfoxide ◽

Structural Data ◽

Redox System ◽

Redox Balance ◽

Rational Drug Design ◽

Sufficient Evidence ◽

Mammalian Host ◽

Neglected Diseases ◽

High Toxicity ◽

Methionine Sulfoxide Reductases

: Chagas Disease, African sleeping sickness, and leishmaniasis are neglected diseases caused by pathogenic trypanosomatid parasites, which have a considerable impact on morbidity and mortality in poor countries. The available drugs used as treatment have high toxicity, limited access, and can cause parasite drug resistance. Long-term treatments, added to their high toxicity, result in patients that give up therapy. Trypanosomatids presents a unique trypanothione based redox system, which is the main responsible for maintaining the redox balance. Therefore, inhibition of these essential and exclusive parasite’s metabolic pathways, absent from the mammalian host, could lead to development of more efficient and safe drugs. The system contains different redox cascades, where trypanothione and tryparedoxins, play together a central role in transferring reduced power to different enzymes, such as 2-Cys peroxiredoxins, non-selenium glutathione peroxidases, ascorbate peroxidases, glutaredoxins and methionine sulfoxide reductases, through NADPH as a source of electrons. There is sufficient evidence that this complex system is essential for parasite survival and infection. In this review, we explore what is known in terms of essentiality, kinetic and structural data, and development of inhibitors of enzymes from this trypanothione-based redox system. The recent advances and limitations in the development of lead inhibitory compounds targeting these enzymes are discussed. The combination of molecular biology, bioinformatics, genomics, and structural biology is fundamental since the knowledge of unique features of the trypanothione-dependent system will provide tools for rational drug design, in order to develop better treatments for these diseases

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Catalytically important damage-free structures of a copper nitrite reductase obtained by femtosecond X-ray laser and room-temperature neutron crystallography

IUCrJ ◽

10.1107/s2052252519008285 ◽

2019 ◽

Vol 6 (4) ◽

pp. 761-772 ◽

Cited By ~ 7

Author(s):

Thomas P. Halsted ◽

Keitaro Yamashita ◽

Chai C. Gopalasingam ◽

Rajesh T. Shenoy ◽

Kunio Hirata ◽

...

Keyword(s):

High Resolution ◽

Resting State ◽

Structural Data ◽

Redox System ◽

X Rays ◽

X Ray ◽

Nitrite Reductases ◽

First Time ◽

Better Than ◽

Neutron Crystallography

Copper-containing nitrite reductases (CuNiRs) that convert NO2−to NO via a CuCAT–His–Cys–CuETproton-coupled redox system are of central importance in nitrogen-based energy metabolism. These metalloenzymes, like all redox enzymes, are very susceptible to radiation damage from the intense synchrotron-radiation X-rays that are used to obtain structures at high resolution. Understanding the chemistry that underpins the enzyme mechanisms in these systems requires resolutions of better than 2 Å. Here, for the first time, the damage-free structure of the resting state of one of the most studied CuNiRs was obtained by combining X-ray free-electron laser (XFEL) and neutron crystallography. This represents the first direct comparison of neutron and XFEL structural data for any protein. In addition, damage-free structures of the reduced and nitrite-bound forms have been obtained to high resolution from cryogenically maintained crystals by XFEL crystallography. It is demonstrated that AspCATand HisCATare deprotonated in the resting state of CuNiRs at pH values close to the optimum for activity. A bridging neutral water (D2O) is positioned with one deuteron directed towards AspCAT Oδ1and one towards HisCAT N∊2. The catalytic T2Cu-ligated water (W1) can clearly be modelled as a neutral D2O molecule as opposed to D3O+or OD−, which have previously been suggested as possible alternatives. The bridging water restricts the movement of the unprotonated AspCATand is too distant to form a hydrogen bond to the O atom of the bound nitrite that interacts with AspCAT. Upon the binding of NO2−a proton is transferred from the bridging water to the Oδ2atom of AspCAT, prompting electron transfer from T1Cu to T2Cu and reducing the catalytic redox centre. This triggers the transfer of a proton from AspCATto the bound nitrite, enabling the reaction to proceed.

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Molecular cloning and characterization of a grapevine (Vitis vinifera L.) serotonin N-acetyltransferase (VvSNAT2) gene involved in plant defense

BMC Genomics ◽

10.1186/s12864-019-6085-3 ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 9

Author(s):

Yihe Yu ◽

Lu Bian ◽

Zeling Jiao ◽

Keke Yu ◽

Yutong Wan ◽

...

Keyword(s):

Transgenic Plants ◽

Vitis Vinifera ◽

Plant Defense ◽

Marker Genes ◽

Vitis Vinifera L ◽

Melatonin Treatment ◽

Gene Encoding ◽

Ja Signaling ◽

First Time

Abstract Background Melatonin is a ubiquitous molecule and exists across kingdoms. Studies on melatonin in plants have mainly focused on its physiological influence on growth and development, and on its biosynthesis. A number of studies have been conducted on the melatonin content and exogenous melatonin treatment of grapevine (Vitis vinifera L.). However, key genes or enzymes of the melatonin biosynthetic pathway remain unclear. Results In this study, we cloned and identified the gene encoding serotonin N-acetyltransferase (SNAT) in grapevine (VvSNAT2). The VvSNAT2 protein was identified from a collection of 30 members of the grapevine GCN5-related N-acetyltransferase (GNAT) superfamily. Phylogenetic and protein sublocalization analyses showed that the candidate gene VvGNAT16 is VvSNAT2. Characterization of VvSNAT2 showed that its enzymatic activity is highest at a pH of 8.8 and a temperature of 45 °C. Analysis of enzyme kinetics showed the values of Km and Vmax of VvSNAT2 using serotonin were 392.5 μM and 836 pmol/min/mg protein, respectively. The expression of VvSNAT2 was induced by melatonin treatment and pathogen inoculation. Overexpression of VvSNAT2 in Arabidopsis resulted in greater accumulation of melatonin and chlorophyll and enhanced resistance to powdery mildew in the transgenic plants compared with the wild type (WT). Additionally, our data showed that the marker genes in the salicylic acid (SA) signaling pathway were expressed to higher levels in the transgenic plants compared with the WT. Conclusions The VvSNAT2 gene was cloned and identified in grapevine for the first time. Our results indicate that VvSNAT2 overexpression activates the SA and JA signaling pathways; however, the SA pathway plays a central role in VvSNAT2-mediated plant defense.

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An update on the occurrence of resistance-breaking populations of root-knot nematodes (Meloidogyne spp.) on resistant tomato in Greece with six new records from Crete

Hellenic Plant Protection Journal ◽

10.1515/hppj-2016-0007 ◽

2016 ◽

Vol 9 (2) ◽

pp. 60-65

Author(s):

E.A. Tzortzakakis ◽

M.-C. Vieira dos Santos ◽

I. Conceição

Keyword(s):

New Records ◽

Vegetable Production ◽

Major Area ◽

Root Knot Nematodes ◽

Resistance Breaking ◽

Meloidogyne Spp ◽

Greenhouse Vegetable ◽

First Time ◽

Greenhouse Vegetable Production

Summary The available published information on the occurrence of resistance-breaking populations of root-knot nematodes (Meloidogyne spp.) on resistant tomato in Greece is updated. Within the period 1994-2013, 13 populations (11 M. javanica and 2 M. incognita) able to reproduce on resistant tomato had been recorded in the regions of Crete, Epirus, Thrace, Peloponissos and Macedonia. In the present study six more resistance-breaking populations, four M. javanica and two M. incognita, were detected in the period 2013-2014, all originating from greenhouse vegetables in Crete. Four of these populations, two M. javanica and two M. incognita, originated from the region of Ierapetra. This is the first time that such populations are found in this major area of greenhouse vegetable production of Crete.

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