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Climate change is significantly impacting agricultural production worldwide. Peanuts provide food and nutritional security to millions of people across the globe because of its high nutritive values. Drought and heat stress alone or in combination cause substantial yield losses to peanut production. The stress, in addition, adversely impact nutritional quality. Peanuts exposed to drought stress at reproductive stage are prone to aflatoxin contamination, which imposes a restriction on use of peanuts as health food and also adversely impact peanut trade. A comprehensive understanding of the impact of drought and heat stress at physiological and molecular levels may accelerate the development of stress tolerant productive peanut cultivars adapted to a given production system. Significant progress has been achieved towards the characterization of germplasm for drought and heat stress tolerance, unlocking the physiological and molecular basis of stress tolerance, identifying significant marker-trait associations as well major QTLs and candidate genes associated with drought tolerance, which after validation may be deployed to initiate marker-assisted breeding for abiotic stress adaptation in peanut. The proof of concept about the use of transgenic technology to add value to peanuts has been demonstrated. Advances in phenomics and artificial intelligence to accelerate the timely and cost-effective collection of phenotyping data in large germplasm/breeding populations have also been discussed. Greater focus is needed to accelerate research on heat stress tolerance in peanut. A suits of technological innovations are now available in the breeders toolbox to enhance productivity and nutritional quality of peanuts in harsh environments. A holistic breeding approach that considers drought and heat-tolerant traits to simultaneously address both stresses could be a successful strategy to produce climate-resilient peanut genotypes with improved nutritional quality.

Peanut (Arachis hypogaea L.), an allotetraploid legume of the Fabaceae family, is able to thrive in tropical and subtropical regions and is considered as a promising oil seed crop worldwide. Increasing the content of oleic acid has become one of the major goals in peanut breeding because of health benefits such as reduced blood cholesterol level, antioxidant properties and industrial benefits such as longer shelf life. Genomic sequencing of peanut has provided evidence of homeologous AhFAD2A and AhFAD2B genes encoding Fatty Acid Desaturase2 (FAD2), which are responsible for catalyzing the conversion of monounsaturated oleic acid into polyunsaturated linoleic acid. Research studies demonstrate that mutations resulting in a frameshift or stop codon in an FAD2 gene leads to higher oleic acid content in oil. In this study, two expression vectors, pDW3873 and pDW3876, were constructed using Cas9 fused to different deaminases, which were tested as tools to induce point mutations in the promoter and the coding sequences of peanut AhFAD2 genes. Both constructs harbor the single nuclease null variant, nCas9 D10A, to which the PmCDA1 cytosine deaminase was fused to the C-terminal (pDW3873) while rAPOBEC1 deaminase and an uracil glycosylase inhibitor (UGI) were fused to the N-terminal and the C-terminal respectively (pDW3876). Three gRNAs were cloned independently into both constructs and the functionality and efficiency were tested at three target sites in the AhFAD2 genes. Both constructs displayed base editing activity in which cytosine was replaced by thymine or other bases in the targeted editing window. pDW3873 showed higher efficiency compared to pDW3876 suggesting that the former is a better base editor in peanut. This is an important step forward considering introgression of existing mutations into elite varieties can take up to 15 years making this tool a benefit for peanut breeders, farmers, industry and ultimately for consumers.

Peanut (Arachis hypogaea L.) seed is a rich source of edible oil, comprised primarily of monounsaturated oleic acid and polyunsaturated linoleic acid, accounting for 80% of its fatty acid repertoire. The conversion of oleic acid to linoleic acid, catalyzed by Fatty Acid Desaturase 2 (FAD2) enzymes, is an important regulatory point linked to improved abiotic stress responses while the ratio of these components is a significant determinant of commercial oil quality. Specifically, oleic acid has better oxidative stability leading to longer shelf life and better taste qualities while also providing nutritional based health benefits. Naturally occurring FAD2 gene knockouts that lead to high oleic acid levels improve oil quality at the potential expense of plant health though. We undertook a CRISPR/Cas9 based site-specific genome modification approach designed to downregulate the expression of two homeologous FAD2 genes in seed while maintaining regulation in other plant tissues. Two cis-regulatory elements the RY repeat motif and 2S seed protein motif in the 5′UTR and associated intron of FAD2 genes are potentially important for regulating seed-specific gene expression. Using hairy root and stable germ line transformation, differential editing efficiencies were observed at both CREs when targeted by single gRNAs using two different gRNA scaffolds. The editing efficiencies also differed when two gRNAs were expressed simultaneously. Additionally, stably transformed seed exhibited an increase in oleic acid levels relative to wild type. Taken together, the results demonstrate the immense potential of CRISPR/Cas9 based approaches to achieve high frequency targeted edits in regulatory sequences for the generation of novel transcriptional alleles, which may lead to fine tuning of gene expression and functional genomic studies in peanut.

Genome-wide association studies (GWAS) have been utilized to detect genetic variations related to several agronomic traits and disease resistance in common bean. However, its application in the powdery mildew (PM) disease to identify candidate genes and their location in the common bean genome has not been fully addressed. Single-nucleotide polymorphism (SNP) genotyping with a BeadChip containing 5398 SNPs was used to detect genetic variations related to PM disease resistance in a panel of 211 genotypes grown under two field conditions for two consecutive years. Significant SNPs identified on chromosomes Pv04 and Pv10 were repeatable, ensuring the phenotypic data’s reliability and the causal relationship. A cluster of resistance genes was revealed on the Pv04 of the common bean genome, coiled-coil-nucleotide-binding site–leucine-rich repeat (CC-NBS-LRR, CNL), and Toll/interleukin-1 receptor-nucleotide-binding site–leucine-rich repeat type (TIR-NBS-LRR, TNL)-like resistance genes were identified. Furthermore, two resistance genes, Phavu_010G1320001g and Phavu_010G136800g, were also identified on Pv10. Further sequence analysis showed that these genes were homologs to the disease-resistance protein (RLM1A-like) and the putative disease-resistance protein (At4g11170.1) in Arabidopsis. Significant SNPs related to two LRR receptor-like kinases (RLK) were only identified on Pv11 in 2018. Many genes encoding the auxin-responsive protein, TIFY10A protein, growth-regulating factor five-like, ubiquitin-like protein, and cell wall RBR3-like protein related to PM disease resistance were identified nearby significant SNPs. These results suggested that the resistance to PM pathogen involves a network of many genes constitutively co-expressed.

Peanuts are an economically important crop cultivated worldwide. However, several limitations restrained its productivity, including biotic/abiotic stresses. CRISPR/Cas9-based gene-editing technology holds a promising approach to developing new crops with improved agronomic and nutritional traits. Its application has been successful in many important crops. However, the application of this technology in peanut research is limited, probably due to the lack of suitable constructs and protocols. In this study, two different constructs were generated to induce insertion/deletion mutations in the targeted gene for a loss of function study. The first construct harbors the regular gRNA scaffold, while the second construct has the extended scaffold plus terminator. The designed gRNA targeting the coding sequence of the FAD2 genes was cloned into both constructs, and their functionality and efficiency were validated using the hairy root transformation system. Both constructs displayed insertions and deletions as the types of edits. The construct harboring the extended plus gRNA terminator showed a higher editing efficiency than the regular scaffold for monoallelic and biallelic mutations. These two constructs can be used for gene editing in peanuts and could provide tools for improving peanut lines for the benefit of peanut breeders, farmers, and industry.

Climate change is significantly impacting agricultural production worldwide. Peanuts provide food and nutritional security to millions of people across the globe because of its high nutritive values. Drought and heat stress alone or in combination cause substantial yield losses to peanut production. The stress, in addition, adversely impact nutritional quality. Peanuts exposed to drought stress at reproductive stage are prone to aflatoxin contamination, which imposes a restriction on use of peanuts as health food and also adversely impact peanut trade. A comprehensive understanding of the impact of drought and heat stress at physiological and molecular levels may accelerate the development of stress tolerant productive peanut cultivars adapted to a given production system. Significant progress has been achieved towards the characterization of germplasm for drought and heat stress tolerance, unlocking the physiological and molecular basis of stress tolerance, identifying significant marker-trait associations as well major QTLs and candidate genes associated with drought tolerance, which after validation may be deployed to initiate marker-assisted breeding for abiotic stress adaptation in peanut. The proof of concept about the use of transgenic technology to add value to peanuts has been demonstrated. Advances in phenomics and artificial intelligence to accelerate the timely and cost-effective collection of phenotyping data in large germplasm/breeding populations have also been discussed. Greater focus is needed to accelerate research on heat stress tolerance in peanut. A suits of technological innovations are now available in the breeders toolbox to enhance productivity and nutritional quality of peanuts in harsh environments. A holistic breeding approach that considers drought and heat-tolerant traits to simultaneously address both stresses could be a successful strategy to produce climate-resilient peanut genotypes with improved nutritional quality. [ABSTRACT FROM AUTHOR]

Peanuts are an economically important crop cultivated worldwide. However, several limitations restrained its productivity, including biotic/abiotic stresses. CRISPR/Cas9-based gene-editing technology holds a promising approach to developing new crops with improved agronomic and nutritional traits. Its application has been successful in many important crops. However, the application of this technology in peanut research is limited, probably due to the lack of suitable constructs and protocols. In this study, two different constructs were generated to induce insertion/deletion mutations in the targeted gene for a loss of function study. The first construct harbors the regular gRNA scaffold, while the second construct has the extended scaffold plus terminator. The designed gRNA targeting the coding sequence of the FAD2 genes was cloned into both constructs, and their functionality and efficiency were validated using the hairy root transformation system. Both constructs displayed insertions and deletions as the types of edits. The construct harboring the extended plus gRNA terminator showed a higher editing efficiency than the regular scaffold for monoallelic and biallelic mutations. These two constructs can be used for gene editing in peanuts and could provide tools for improving peanut lines for the benefit of peanut breeders, farmers, and industry. [ABSTRACT FROM AUTHOR]

Peanut (Arachis hypogaea L.) seed is a rich source of edible oil, comprised primarily of monounsaturated oleic acid and polyunsaturated linoleic acid, accounting for 80% of its fatty acid repertoire. The conversion of oleic acid to linoleic acid, catalyzed by Fatty Acid Desaturase 2 (FAD2) enzymes, is an important regulatory point linked to improved abiotic stress responses while the ratio of these components is a significant determinant of commercial oil quality. Specifically, oleic acid has better oxidative stability leading to longer shelf life and better taste qualities while also providing nutritional based health benefits. Naturally occurring FAD2 gene knockouts that lead to high oleic acid levels improve oil quality at the potential expense of plant health though. We undertook a CRISPR/Cas9 based site-specific genome modification approach designed to downregulate the expression of two homeologous FAD2 genes in seed while maintaining regulation in other plant tissues. Two cis -regulatory elements the RY repeat motif and 2S seed protein motif in the 5′UTR and associated intron of FAD2 genes are potentially important for regulating seed-specific gene expression. Using hairy root and stable germ line transformation, differential editing efficiencies were observed at both CREs when targeted by single gRNAs using two different gRNA scaffolds. The editing efficiencies also differed when two gRNAs were expressed simultaneously. Additionally, stably transformed seed exhibited an increase in oleic acid levels relative to wild type. Taken together, the results demonstrate the immense potential of CRISPR/Cas9 based approaches to achieve high frequency targeted edits in regulatory sequences for the generation of novel transcriptional alleles, which may lead to fine tuning of gene expression and functional genomic studies in peanut. [ABSTRACT FROM AUTHOR]

La mesure de l'insecurite alimentaire est la preoccupation majeure des pays du Sahel comme le Burkina Faso pour anticiper les crises. Ce travail a pour objectif de determiner les relations entre les variables collectees regulierement par les systemes d'information nationaux et les resultats primaires de la securite alimentaire que sont la consommation alimentaire des menages et revolution des avoirs relatifs aux moyens d'existence. Cela permet aux analystes de suivre et d'informer rapidement sur revolution de la situation alimentaire et de faciliter la prise de decision. Ces informations permettront egalement d'orienter la reponse en direction des populations les plus affectees. Les resultats des enquetes de vulnerabilite conduites au Burkina Faso sur plus de 20000 menages en 2016, 2017 et 2018 et representatifs au niveau provincial ont servi de base de travail. Des analyses de correlation et de regression ont ete effectuees entre la production cerealiere totale, la variation annuelle de la production, les prix des cereales, les depenses alimentaires des menages d'une part, et les indices d'evaluation de l'insecurite alimentaire (indice des strategies d'adaptation basees sur la consommation alimentaire, et strategies d'adaptation basees sur les moyens de subsistance) d'autre part. Les bonnes productions agricoles cerealieres de la province influencent positivement le niveau de consommation alimentaire des menages et reduisent leur recours a des strategies extremes basees sur les moyens d'existence et sur la consommation alimentaire. Le prix eleve des cereales et sa forte variation impactent negativement les moyens de subsistance et la consommation alimentaire des menages, tout en accentuant leur recours a des strategies extremes d'adaptation, surtout dans les zones de faible production cerealiere. En plus, lorsque les depenses alimentaires des menages sont inferieures a 50% des depenses totales, cela favorise la preservation des moyens de subsistance et ameliore leur consommation alimentaire. A l'inverse, lorsque les depenses sont superieures a 75%, la vulnerabilite des menages face a la baisse de la production agricole et a la hausse des prix des cereales est accentuee. Les niveaux de correlation observes entre les variables etudiees sont dans l'ensemble relativement faibles, mais leur combinaison permet d'ameliorer significativement les regressions. Une etude a l'echelle de la region devrait permettre de degager des relations plus interessantes. [ABSTRACT FROM AUTHOR]

Genome-wide association studies (GWAS) have been utilized to detect genetic variations related to several agronomic traits and disease resistance in common bean. However, its application in the powdery mildew (PM) disease to identify candidate genes and their location in the common bean genome has not been fully addressed. Single-nucleotide polymorphism (SNP) genotyping with a BeadChip containing 5398 SNPs was used to detect genetic variations related to PM disease resistance in a panel of 211 genotypes grown under two field conditions for two consecutive years. Significant SNPs identified on chromosomes Pv04 and Pv10 were repeatable, ensuring the phenotypic data's reliability and the causal relationship. A cluster of resistance genes was revealed on the Pv04 of the common bean genome, coiled-coil-nucleotide-binding site–leucine-rich repeat (CC-NBS-LRR, CNL), and Toll/interleukin-1 receptor-nucleotide-binding site–leucine-rich repeat type (TIR-NBS-LRR, TNL)-like resistance genes were identified. Furthermore, two resistance genes, Phavu_010G1320001g and Phavu_010G136800g , were also identified on Pv10. Further sequence analysis showed that these genes were homologs to the disease-resistance protein (RLM1A-like) and the putative disease-resistance protein (At4g11170.1) in Arabidopsis. Significant SNPs related to two LRR receptor-like kinases (RLK) were only identified on Pv11 in 2018. Many genes encoding the auxin-responsive protein, TIFY10A protein, growth-regulating factor five-like, ubiquitin-like protein, and cell wall RBR3-like protein related to PM disease resistance were identified nearby significant SNPs. These results suggested that the resistance to PM pathogen involves a network of many genes constitutively co-expressed. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin de la Société de Pathologie Exotique is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Bacterial fruit blotch (BFB) caused by Acidovorax citrulli is one of the most important bacterial diseases of cucurbits worldwide. However, the mechanisms associated with A. citrulli pathogenicity and genetics of host resistance have not been extensively investigated. We idenitfied Nicotiana benthamiana and Nicotiana tabacum as surrogate hosts for studying A. citrulli pathogenicity and non‐host resistance triggered by type III secreted (T3S) effectors. Two A. citrulli strains, M6 and AAC00‐1, that represent the two major groups amongst A. citrulli populations, induced disease symptoms on N. benthamiana, but triggered a hypersensitive response (HR) on N. tabacum plants. Transient expression of 19 T3S effectors from A. citrulli in N. benthamiana leaves revealed that three effectors, Aave_1548, Aave_2708, and Aave_2166, trigger water‐soaking‐like cell death in N. benthamiana. Aave_1548 knockout mutants of M6 and AAC00‐1 displayed reduced virulence on N. benthamiana and melon (Cucumis melo L.). Transient expression of Aave_1548 and Aave_2166 effectors triggered a non‐host HR in N. tabacum, which was dependent on the functionality of the immune signalling component, NtSGT1. Hence, employing Nicotiana species as surrogate hosts for studying A. citrulli pathogenicity may help characterize the function of A. citrulli T3S effectors and facilitate the development of new strategies for BFB management. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin de la Société de Pathologie Exotique is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Long noncoding RNAs (lncRNAs) have several known functions involving various biological regulatory processes in plant. However, the possible roles of lncRNAs during peanut seed development have not been fully explored. Results In this study, two peanut recombinant inbred lines (RIL8) that differ in seed size were used to investigate comprehensive lncRNA profiles derived from the seed development at 15 and 35 days after flowering (DAF). We identified a total of 9388 known and 4037 novel lncRNAs, from which 1437 were differentially expressed lncRNAs. Interestingly, the expression patterns of a number of lncRNAs can be very different between two closely related inbred lines and these lncRNAs were expressed predominantly in only one RIL at 35 DAF. Some differentially expressed lncRNAs were found related to putative cis-acting target genes and predicted to be involved in transcription, transport, cell division, and plant hormone biosynthesis. The expression patterns of several representative lncRNAs and 12 protein-coding genes were validated by qPCR. Same expression pattern was observed between most lncRNAs and their target genes. 11 lncRNAs, XR_001593099.1, MSTRG.18462.1, MSTRG.34915.1, MSTRG.41848.1, MSTRG.22884.1, MSTRG.12404.1, MSTRG.26719.1, MSTRG.35761.1, MSTRG.20033.1, MSTRG.13500.1, and MSTRG.9304.1 and their cis-acting target genes may play key roles in peanut seed development. Conclusions These results provided new information on lncRNA-mediated regulatory roles in peanut seed development, contributing to the comprehensive understanding of the molecular mechanisms involved in peanut seed development.

Copyright of Andrologie (11662654) is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Education for Health: Change in Learning & Practice is the property of Wolters Kluwer India Pvt Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fast neutron irradiation was used to improve the switching speed of a 600-V nonpunch-through insulated gate bipolar transistor. Fast neutron irradiation was carried out at 30-MeV energy in doses of 1 × 108 n/cm2, 1 × 109 n/cm2, 1 × 1010 n/cm2, and 1 × 1011 n/cm2. Electrical characteristics such as current–voltage, forward on-state voltage drop, and switching speed of the device were analyzed and compared with those prior to irradiation. The on-state voltage drop of the initial devices prior to irradiation was 2.08 V, which increased to 2.10 V, 2.20 V, 2.3 V, and 2.4 V, respectively, depending on the irradiation dose. This effect arises because of the lattice defects generated by the fast neutrons. In particular, the turnoff delay time was reduced to 92 nanoseconds, 45% of that prior to irradiation, which means there is a substantial improvement in the switching speed of the device.

In this paper, we give some mathematical results for a system of partial differential equations arising for instance in oceanography and meteorology. This model is called the planetary geostrophic equations or thermohaline equations. Different systems exist depending on the different viscous operators used to parameterize the small-scale processes. These choices made by physicists are empirical and are subject to numerous numerical studies. These parametrizations sometimes provide some models like Bénard convection in a rotating thin porous medium. Unfortunately this observation seems to be unknown to people working on geophysical fluid dynamics. Thus, in a first section, we discuss models which are sometimes known by several names. We compare the results obtained by people working on porous media and by people working on geophysical fluid dynamics. The last section is devoted to mathematical results. More precisely, we prove that it is possible in particular domains to extend some recent mathematical results by the use of some simple relations between the vertical velocity and the temperature. Many applications exist with such domains in meteorology. This system is also used in the food processing industry or in centrifugal filtration processes. In the last part, we indicate how to extend the results to a domain with a vanishing depth on the shore in the case of the hyperviscous parametrization. This has some applications in oceanography for instance. [ABSTRACT FROM AUTHOR]

Prion diseases are characterized by the conversion of the normal cellular prion protein (PrP[sup C]) into a pathogenic isoform (PrP[sup Sc]). PrP[sup C] binds copper, has superoxide dismutase (SOD)-like activity in vitro, and its expression aids in the cellular response to oxidative stress. However, the interplay between PrPs (PrP[sup C], PrP[sup Sc] and possibly other abnormal species), copper, anti-oxidation activity and pathogenesis of prion diseases remain unclear. In this study, we reported dramatic depression of SOD-like activity by the affinity-purified PrPs from scrapie-infected brains, and together with significant reduction of Cu/Zn-SOD activity, correlates with significant perturbations in the divalent metals contents. We also detected elevated levels of nitric oxide and superoxide in the infected brains, which could be escalating the oxidative modification of cellular proteins, reducing gluathione peroxidase activity and increasing the levels of lipid peroxidation markers. Taken together, our results suggest that brain metal imbalances, especially copper, in scrapie infection is likely to affect the anti-oxidation functions of PrP and SODs, which, together with other cellular dysfunctions, predispose the brains to oxidative impairment and eventual degeneration. To our knowledge, this is the first study documenting a physiological connection between brain metals imbalances, the anti-oxidation function of PrP, and aberrations in the cellular responses to oxidative stress, in scrapie infection. [ABSTRACT FROM AUTHOR]

Human prion diseases are characterized by the conversion of the normal prion protein (PrP[sup C]) into a pathogenic isomer (PrP[sup Sc]). Distinct PrP[sup Sc] conformers are associated with different subtypes of prion diseases. PrP[sup C] binds copper and has antioxidation activity. Changes in metal-ion occupancy can lead to significant decline of the antioxidation activity and changes in conformation of the protein. We studied the trace element status of brains from patients with sporadic Creutzfeldt–Jakob disease (sCJD). We found a decrease of up to 50% of copper and an increase in manganese of approximately 10-fold in the brain tissues from sCJD subjects. We have also studied the metal occupancy of PrP in sCJD patients. We observed striking elevation of manganese and, to a lesser extent, of zinc accompanied by significant reduction of copper bound to purified PrP in all sCJD variants, determined by the PrP genotype and PrP[sup Sc] type, combined. Both zinc and manganese were undetectable in PrP[sup C] preparations from controls. Copper and manganese changes were pronounced in sCJD subjects homozygous for methionine at codon 129 and carrying PrP[sup Sc] type-1. Anti-oxidation activity of purified PrP was dramatically reduced by up to 85% in the sCJD variants, and correlated with increased in oxidative stress markers in sCJD brains. These results suggest that altered metal-ion occupancy of PrP plays a pivotal role in the pathogenesis of prion diseases. Since the metal changes differed in each sCJD variants, they may contribute to the diversity of PrP[sup Sc] and disease phenotype in sCJD. Finally, this study also presented two potential approaches in the diagnosis of CJD; the significant increase in brain manganese makes it potentially detectable by MRI, and the binding of manganese by PrP in sCJD might represent a novel diagnostic marker. [ABSTRACT FROM AUTHOR]

Although minor abnormalities have been reported in prion protein (PrP) knock-out (Prnp[sup -/–]) mice, the normal physiological function of PrP, the causative agent implicated in transmissible spongiform encephalopathies (TSE), remains unresolved. Since there are increasing correlations between oxidative stress and amyloidoses, we decided to investigate whether PrP plays a role in oxidative modulation. We found higher levels of oxidative damage to proteins and lipids in the brain lysates of Prnp[sup -/–] as compared to wild-type (WT) mice of the same genetic background. These two indicators, protein oxidation and lipid peroxidation, are hallmarks of cellular oxidative damage. Elevated levels of ubiquitin-protein conjugates were also observed in Prnp[sup -/–] mice, a probable consequence of cellular attempts to remove the damaged proteins as indicated by increased proteasome activity. Taken together, these findings are indicative of a role for PrP in oxidative homeostasis in vivo. [ABSTRACT FROM AUTHOR]

ABSTRACT Marek’s disease virus (MDV) has been shown to be evolving to higher virulence. One of the genetic sites involved in virulence which enables such characterization is the 339-amino acid Meq protein encoding gene (meq). The reemergence of clinical Marek’s disease (MD) in vaccinated flocks can be associated to changes in meq. Our studies have shown the presence of very virulent MDV strains in the Brazilian industrial and free-range poultry. We present an overview of MD increasing severity and indicate the necessity of using phylogenetic tools for best accompanying MDV evolution.

ABSTRACT The incidence of the psittacine beak and feather disease virus (BFDV) was investigated in Brazilian native parrots with normal feathering arriving at rescue and triage centers for wild animals (CETAS, IBAMA) in the state of Minas Gerais, Brazil. BFDV DNA was investigated by previously described PCR technique for the partial amplification of BFDV ORF-1 in DNA extracts from blood, cloacal swab or liver of psittacines. Some birds provided more than one sample. Nine species of psittacines were sampled between January 2009 and October 2010. Blood (n=46) or cloacal swab (n=128) samples were obtained from psittacines immediately upon arrival at the triage centers. Liver samples were collected from necropsied birds dead on arrival (n=167). All swab samples were negative, except for one Ara ararauna individual (n=3) which blood presented the BFDV DNA. On the other hand, 11 liver samples were positive for BFDV DNA, with a prevalence of 7.8% in Amazona aestiva (n=140). No BFDV DNA was detected in the liver of Amazona amazonica (n=11), A. vinacea (n=5), A. rhodochorytha (n=4), Anodorhynchus hyacinthinus (n=3), Ara ararauna, (n=3), Aratinga leucophtalma (n=2), Guarouba guarouba (n=1) and Pionus maximiliani (n=1). In most cases, alopecia was not associated with BFDV detection in liver, and liver histopathology was inconclusive. Although all cloacal swab samples were negative, a few psittacines (n=19) that died at CETAS-Belo Horizonte were retested, and 21% were detected as positive in liver. A group of psittacines (n=16) was clinically evaluated, and despite showing feather dystrophy, all birds were negative in the cloacal swabs, except for one, which blood sample was positive (A. ararauna). The obtained sequences of the BFDV strains BH 215 and BH 732 were deposited in the GenBank (JQ649409 and JQ649410). A 98% similarity with strain sequences described in Australia, Japan, and New Zealand was observed. It is possible that these strains arrived in Brazil through the legal and illegal trade of parrots. However, it was not possible to associate BFDV infection with the geographical origin of birds and no local marker was detected. The rates of detection, although similar to other studies, indicate the tendency of a high incidence of the disease, possibly associated with stress, and high bird density and wide transmission in captivity conditions.

A high CO2 concentration (20%) at 20°C rapidly and strongly inhibited the development of the climacteric ethylene burst in apple (Malus domestica Borkh. cv. Granny Smith) and avocado (Persea americana Mill. cv. Fuerte) fruits and did not change 1-aminocyclopropane-1-carboxylic acid (ACC) content. Treatment with 20% CO2 markedly decreased ACC-dependent ethylene biosynthesis at 20°C in climacteric pericarp tissues. It is suggested, therefore, that high CO2 levels inhibit conversion of ACC to ethylene. Synthesis of the ethylene forming enzyme (EFE) was enhanced when intact preclimacteric apples or early climacteric avocados were pretreated for 40 h with 10 μl l-1 ethylene. When CO2 (20%) and ethylene were both applied, a reduced stimulatory effect of ethylene on EFE synthesis was observed. A high CO2 concentration enhanced EFE acivity in excised tissues of apples and avocados incubated with ACC (2 mM) and cycloheximide (1 mM) or 2-5-norbornadiene (5 ml l-1). In the autocatalytic process, 20% CO2 antagonized the stimulation of EFE synthesis by ethylene, but promoted EFE activity.