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Molnupiravir is an antiviral that forces lethal error catastrophe in SARS-CoV-2 RNAs. Here, the authors confirm the mechanism of action of molnupiravir in humans using samples obtained from the UK’s AGILE phase IIa clinical trial investigating the antiviral efficacy of the drug against SARS-CoV-2. No treatment-associated SARS-CoV-2 mutations were identified.

Protein transporters move essential metabolites across membranes in all living organisms. Downy mildew causing plant pathogens are biotrophic oomycetes that transport essential nutrients from their hosts to grow. Little is known about the functions and gene expression levels of membrane transporters produced by downy mildew causing pathogens during infection of their hosts. Approximately 170-190 nonredundant transporter genes were identified in the genomes of Peronospora belbahrii, Peronospora effusa, and Peronospora tabacina, which are specialized pathogens of basil, spinach, and tobacco, respectively. The largest groups of transporter genes in each species belonged to the major facilitator superfamily, mitochondrial carriers (MC), and the drug/metabolite transporter group. Gene expression of putative Peronospora transporters was measured using RNA sequencing data at two time points following inoculation onto leaves of their hosts. There were 16 transporter genes, seven of which were MCs, expressed in each Peronospora species that were among the top 45 most highly expressed transporter genes 5-7 days after inoculation. Gene transcripts encoding the ADP/ATP translocase and the mitochondrial phosphate carrier protein were the most abundant mRNAs detected in each Peronospora species. This study found a number of Peronospora genes that are likely critical for pathogenesis and which might serve as future targets for control of these devastating plant pathogens.

Abstract Background There is an urgent unmet clinical need for the identification of novel therapeutics for the treatment of COVID-19. A number of COVID-19 late phase trial platforms have been developed to investigate (often repurposed) drugs both in the UK and globally (e.g. RECOVERY led by the University of Oxford and SOLIDARITY led by WHO). There is a pressing need to investigate novel candidates within early phase trial platforms, from which promising candidates can feed into established later phase platforms. AGILE grew from a UK-wide collaboration to undertake early stage clinical evaluation of candidates for SARS-CoV-2 infection to accelerate national and global healthcare interventions. Methods/design AGILE is a seamless phase I/IIa platform study to establish the optimum dose, determine the activity and safety of each candidate and recommend whether it should be evaluated further. Each candidate is evaluated in its own trial, either as an open label single arm healthy volunteer study or in patients, randomising between candidate and control usually in a 2:1 allocation in favour of the candidate. Each dose is assessed sequentially for safety usually in cohorts of 6 patients. Once a phase II dose has been identified, efficacy is assessed by seamlessly expanding into a larger cohort. AGILE is completely flexible in that the core design in the master protocol can be adapted for each candidate based on prior knowledge of the candidate (i.e. population, primary endpoint and sample size can be amended). This information is detailed in each candidate specific trial protocol of the master protocol. Discussion Few approved treatments for COVID-19 are available such as dexamethasone, remdesivir and tocilizumab in hospitalised patients. The AGILE platform aims to rapidly identify new efficacious and safe treatments to help end the current global COVID-19 pandemic. We currently have three candidate specific trials within this platform study that are open to recruitment. Trial registration EudraCT Number: 2020-001860-27 14 March 2020 ClinicalTrials.gov Identifier: NCT04746183 19 February 2021 ISRCTN reference: 27106947

Peronospora effusa is an obligate pathogen that causes downy mildew on spinach and is considered the most economically important disease of spinach. The objective of the current research was to assess genetic diversity of known historical races and isolates collected in 2014 from production fields in Yuma, Arizona and Salinas Valley, California. Candidate neutral single nucleotide polymorphisms (SNPs) were identified by comparing sequence data from reference isolates of known races of the pathogen collected in 2009 and 2010. Genotypes were assessed using targeted sequencing on genomic DNA extracted directly from infected plant tissue. Genotyping 26 historical and 167 contemporary samples at 46 SNP loci revealed 82 unique multi-locus genotypes. The unique genotypes clustered into five groups and the majority of isolates collected in 2014 were genetically closely related, regardless of source location. The historical samples, representing several races, showed greater genetic differentiation. Overall, the SNP data indicate much of the genotypic variation found within fields was produced during asexual development, whereas overall genetic diversity may be influenced by sexual recombination on broader geographical and temporal scales.

Abstract Background Rural women are more likely to be obese and have a higher risk for chronic disease than their non-rural counterparts. Inadequate physical activity (PA) at least in part contributes to this increased risk. Rural women face personal, social and environmental barriers to PA engagement. Interventions promoting walking among rural women have demonstrated success; however, few of these studies use text messaging to promote PA. Methods Step-2-It was a pilot study to assess the feasibility, acceptability, and effectiveness of text-messaging combined with a pedometer to promote PA, specifically walking among English-speaking women, aged 40 and older, living in a rural, northwest Illinois county. Enrolled participants completed baseline assessments, received pedometers and two types of automated text messages: motivational messages to encourage walking, and accountability messages to report pedometer steps. Participants engaged in 3, 6, 9, and 12-week follow-ups to download pedometer data, and completed post-intervention assessments at 12 weeks. Results Of the 44 enrolled participants, 35 participants (79.5%) completed the intervention. Among completers, the proportion meeting PA guidelines increased from 31.4% (11/35) at baseline to 48.6% (17/35) at post-intervention, those with no PA decreased from 20% (7/35) to 17.1% (6/35). During weeks 1-12, when participants received motivational text messages, average participant daily step count was 5926 ± 3590, and remained stable during the intervention. Pedometer readings were highly correlated with self-reported steps (r = 0.9703; p < 0.001). Conclusion Step-2-It was a feasible and acceptable walking intervention for older rural women. Technology, including text messaging, should be investigated further as an enhancement to interventions for rural women. Trial Registration on Clinicaltrials.gov: NCT04812756, registered on March 22, 2021

Fusarium wilt of banana is a devastating disease that has decimated banana production worldwide. Host resistance to Fusarium oxysporum f. sp. Cubense (Foc), the causal agent of this disease, is genetically dissected in this study using two Musa acuminata ssp. Malaccensis segregating populations, segregating for Foc Tropical (TR4) and Subtropical (STR4) race 4 resistance. Marker loci and trait association using 11 SNP-based PCR markers allowed the candidate region to be delimited to a 12.9 cM genetic interval corresponding to a 959 kb region on chromosome 3 of ‘DH-Pahang’ reference assembly v4. Within this region, there was a cluster of pattern recognition receptors, namely leucine-rich repeat ectodomain containing receptor-like protein kinases, cysteine-rich cell-wall-associated protein kinases, and leaf rust 10 disease-resistance locus receptor-like proteins, positioned in an interspersed arrangement. Their transcript levels were rapidly upregulated in the resistant progenies but not in the susceptible F2 progenies at the onset of infection. This suggests that one or several of these genes may control resistance at this locus. To confirm the segregation of single-gene resistance, we generated an inter-cross between the resistant parent ‘Ma850’ and a susceptible line ‘Ma848’, to show that the STR4 resistance co-segregated with marker ‘28820’ at this locus. Finally, an informative SNP marker 29730 allowed the locus-specific resistance to be assessed in a collection of diploid and polyploid banana plants. Of the 60 lines screened, 22 lines were predicted to carry resistance at this locus, including lines known to be TR4-resistant, such as ‘Pahang’, ‘SH-3362’, ‘SH-3217’, ‘Ma-ITC0250’, and ‘DH-Pahang/CIRAD 930’. Additional screening in the International Institute for Tropical Agriculture’s collection suggests that the dominant allele is common among the elite ‘Matooke’ NARITA hybrids, as well as in other triploid or tetraploid hybrids derived from East African highland bananas. Fine mapping and candidate gene identification will allow characterization of molecular mechanisms underlying the TR4 resistance. The markers developed in this study can now aid the marker-assisted selection of TR4 resistance in breeding programs around the world.

Persistent organic pollutants are stored in environmental reservoirs globally. Tracking the mass and movement of these pollutants is critical for assessing environmental health for human and wildlife populations. Recently, glaciers have been identified as secondary reservoirs for persistent organic pollutants. Downstream lakes and rivers have increased risk of exposure with climate change and loss of glacier mass. Two glaciers, Palisade and Middle Palisade Glaciers, in the Sierra Nevada Mountains, California, United States, were modeled for total mass of the persistent organic pollutant, 4-nonylphenol (4NP). The model used LiDAR measurements of surface snow and geographic information systems (GIS) to extrapolate vertical and horizontal 4NP gradients. Concentrations of 4NP in surface snow were sampled in locations based on a range of topographical shielding indices and analyzed via gas chromatography–mass spectrometry. The Middle Palisade Glacier, the smaller and more shielded glacier, had a total mass of 1,677 ± 560 kg 4NP/km2. The Palisade Glacier, which is larger and more exposed to atmospheric deposition, held an estimated 3,456 ± 843 kg 4NP/km2. Meltwater concentrations for the Middle Palisade and Palisade Glaciers were 1.3 ± 0.05 μg/L and 6.1 ± 1.3 μg/L, respectively. These values demonstrate that both glaciers store a significant amount of 4NP and will act as secondary sources of 4NP for downstream water bodies.

Vascular wilt caused by the ascomycete fungal pathogen Fusarium oxysporum f. sp. cubense (Foc) is a major constraint of banana production around the world. The virulent race, namely Tropical Race 4, can infect all Cavendish-type banana plants and is now widespread across the globe, causing devastating losses to global banana production. In this study, we characterized Foc Subtropical Race 4 (STR4) resistance in a wild banana relative which, through estimated genome size and ancestry analysis, was confirmed to be Musa acuminata ssp. malaccensis. Using a self-derived F2 population segregating for STR4 resistance, quantitative trait loci sequencing (QTL-seq) was performed on bulks consisting of resistant and susceptible individuals. Changes in SNP index between the bulks revealed a major QTL located on the distal end of the long arm of chromosome 3. Multiple resistance genes are present in this region. Identification of chromosome regions conferring resistance to Foc can facilitate marker assisted selection in breeding programs and paves the way towards identifying genes underpinning resistance.

Abstract Background Campylobacter is the leading cause of bacterial gastroenteritis worldwide, and contaminated chicken is a significant vehicle for spread of the disease. This study aimed to assess consumers’ knowledge of safe chicken handling practices and whether their expectations for food safety labelling of chicken are met, as a strategy to prevent campylobacteriosis. Methods We conducted a cross-sectional survey of 401 shoppers at supermarkets and butcheries in Wellington, New Zealand, and a systematic assessment of content and display features of chicken labels. Results While 89% of participants bought, prepared or cooked chicken, only 15% knew that most (60–90%) fresh chicken in New Zealand is contaminated by Campylobacter. Safety and correct preparation information on chicken labels, was rated ‘very necessary’ or ‘essential’ by the majority of respondents. Supermarket chicken labels scored poorly for the quality of their food safety information with an average of 1.7/5 (95% CI, 1.4–2.1) for content and 1.8/5 (95% CI, 1.6–2.0) for display. Conclusions Most consumers are unaware of the level of Campylobacter contamination on fresh chicken and there is a significant but unmet consumer demand for information on safe chicken preparation on labels. Labels on fresh chicken products are a potentially valuable but underused tool for campylobacteriosis prevention in New Zealand.

Members of the Fusarium oxysporum species complex include pathogenic and non-pathogenic isolates and infect a broad range of plant species. F. oxysporum f. sp. cubense (Foc) causes the destructive Fusarium wilt of banana, and the recently emerged Foc tropical race 4 strain threatens the global banana industry. Secreted in xylem (SIX) genes encode for F. oxysporum effector proteins that are associated with virulence in pathogenic F. oxysporum, however they have rarely been reported from non-pathogenic F. oxysporum isolates. Our recent survey of asymptomatic banana plants grown in Foc-infested fields in Queensland and northern NSW revealed that diverse Fusarium spp, including F. oxysporum, reside in the plant roots and pseudostem without causing obvious damage to the plant. Intriguingly, we amplified SIX genes from several of the putative endophytic F. oxysporum isolates identified in the survey and found that they differ in their profile to known Foc SIX genes. To study the role of the endophytic F. oxysporum isolates in planta and the biological function of their SIX genes in more detail, we will re-inoculate cultivated and wild diploid banana lines with the endophytic F. oxysporum strains under glasshouse conditions to assess if they are non-pathogenic on banana. Secondly, we will determine whether the endophytic F. oxysporum SIX genes are expressed in planta and/or in vitro and look at the transcriptome changes occurring in the host following infection. Finally, endophytic F. oxysporum strains transformed with GFP will be used to investigate the extent of fungal colonisation in the plant.

Some of the most devastating agricultural diseases are caused by root-infecting pathogens, yet the majority of studies on these interactions to date have focused on the host responses of aerial tissues rather than those belowground. Fusarium oxysporum is a root-infecting pathogen that causes wilt disease on several plant species including Arabidopsis thaliana. To investigate and compare transcriptional changes triggered by F. oxysporum in different Arabidopsis tissues, we infected soil-grown plants with F. oxysporum and subjected root and leaf tissue harvested at early and late timepoints to RNA-seq analyses. At least half of the genes induced or repressed by F. oxysporum showed tissue-specific regulation. Regulators of auxin and ABA signalling, mannose binding lectins and peroxidases showed strong differential expression in root tissue. We demonstrate that ARF2 and PRX33, two genes regulated in the roots, promote susceptibility to F. oxysporum. In the leaves, defensins and genes associated with the response to auxin, cold and senescence were strongly regulated while jasmonate biosynthesis and signalling genes were induced throughout the plant.

Plants respond to pathogens either by investing more resources into immunity which is costly to development, or by accelerating reproductive processes such as flowering time to ensure reproduction occurs before the plant succumbs to disease. In this study we explored the link between flowering time and pathogen defense using the interaction between Arabidopsis thaliana and the root infecting fungal pathogen Fusarium oxysporum. We report that F. oxysporum infection accelerates flowering time and regulates transcription of a number of floral integrator genes, including FLOWERING LOCUS C (FLC), FLOWERING LOCUS T (FT) and GIGANTEA (GI). Furthermore, we observed a positive correlation between late flowering and resistance to F. oxysporum in A. thaliana natural ecotypes. Late-flowering gi and autonomous pathway mutants also exhibited enhanced resistance to F. oxysporum, supporting the association between flowering time and defense. However, epistasis analysis showed that accelerating flowering time by deletion of FLC in fve-3 or fpa-7 mutants did not alter disease resistance, suggesting that the effect of autonomous pathway on disease resistance occurs independently from flowering time. Indeed, RNA-seq analyses suggest that fve-3 mediated resistance to F. oxysporum is most likely a result of altered defense-associated gene transcription. Together, our results indicate that the association between flowering time and pathogen defense is complex and can involve both pleiotropic and direct effects.