The Role of Insect Cytochrome P450s in Mediating Insecticide Resistance

In many organisms, cytochrome P450 enzymes are the primary detoxifying enzymes. Enhanced P450 activity can be mediated by the emergence of new genes, increased transcription due to mutations in the promoter regions, changes in enzyme structures and functions due to mutations in protein-coding regions, or changes in post-translational modifications; all of these changes are subject to insecticide selection pressure. Multiple signalling pathways and key effector molecules are involved in the regulation of insect P450s. Increased P450 activity is a key mechanism inducing insect resistance. Hence, downregulation of selected P450s is a promising strategy to overcome this resistance. Insect P450 inhibitors that act as insecticide synergists, RNA interference to induce P450 gene silencing, and the use of transgenic insects and crops are examples of strategies utilized to overcome resistance. This article reviews the latest advances in studies related to insect P450s-mediated agrochemical resistance, with focuses on the regulatory mechanisms and associated pest management strategies. Future investigations on the comprehensive regulatory pathways of P450-mediated detoxification, identification of key effectors, and downregulation strategies for P450s will ecologically, economically, and practically improve pest management.

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Soil Nitrogen Movement under Sustainable Vegetable Production Systems

HortScience ◽

10.21273/hortsci.33.3.494f ◽

1998 ◽

Vol 33 (3) ◽

pp. 494f-495 ◽

Cited By ~ 1

Author(s):

Amy M. Johnson ◽

Greg D. Hoyt

Keyword(s):

Pest Management ◽

Soil Nitrogen ◽

Conservation Tillage ◽

Management Strategies ◽

Conventional Tillage ◽

Plant Diseases ◽

Vegetable Production ◽

Beneficial Arthropods ◽

Weed Species ◽

Available Nitrogen

An experiment was established to determine the effect of different tillage practices, vegetable crop rotations, and pest management strategies on crop yield, plant diseases, pest and beneficial arthropods, weed species changes over time, and soil environmental consequences. This poster describes nitrogen movement from the various treatments over a 3-year rotation. The treatments are: 1) conventional tillage with chemically based IPM; 2) conventional tillage with biologically based IPM; 3) conservation tillage with chemically based IPM; 4) conservation tillage with biologically based IPM; and 5) conventional tillage with no fertilizer or pest management. Mid-season soil analyses with depth showed chemical-fertilized plowed and conservation-tilled treatments with more soil available nitrogen at most depths compared to the biological-based IPM systems (soybean meal was used as a nitrogen source). However, the biological-based systems did supply enough soil nitrogen to produce similar yield results as the chemical-based systems. Less soil nitrate was measured in the 30- to 90-cm depths at harvest from the biological-based systems than chemical-based systems. Conservation-tilled systems had greater nitrate with depth compared to conventional-tilled systems.

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ZFARED: A Database of the Antioxidant Response Elements in Zebrafish

Current Bioinformatics ◽

10.2174/1574893614666191018172213 ◽

2020 ◽

Vol 15 (5) ◽

pp. 415-419

Author(s):

Azhwar Raghunath ◽

Raju Nagarajan ◽

Ekambaram Perumal

Keyword(s):

Target Genes ◽

Antioxidant Response ◽

Zebrafish Genome ◽

Promoter Regions ◽

Protein Coding ◽

Response Elements ◽

Toxic Agents ◽

Upstream Promoter ◽

Its Gene ◽

Antioxidant Response Elements

Background: Antioxidant Response Elements (ARE) play a key role in the expression of Nrf2 target genes by regulating the Keap1-Nrf2-ARE pathway, which offers protection against toxic agents and oxidative stress-induced diseases. Objective: To develop a database of putative AREs for all the genes in the zebrafish genome. This database will be helpful for researchers to investigate Nrf2 regulatory mechanisms in detail. Methods: To facilitate researchers functionally characterize zebrafish AREs, we have developed a database of AREs, Zebrafish Antioxidant Response Element Database (ZFARED), for all the protein-coding genes including antioxidant and mitochondrial genes in the zebrafish genome. The front end of the database was developed using HTML, JavaScript, and CSS and tested in different browsers. The back end of the database was developed using Perl scripts and Perl-CGI and Perl- DBI modules. Results: ZFARED is the first database on the AREs in zebrafish, which facilitates fast and efficient searching of AREs. AREs were identified using the in-house developed Perl algorithms and the database was developed using HTML, JavaScript, and Perl-CGI scripts. From this database, researchers can access the AREs based on chromosome number (1 to 25 and M for mitochondria), strand (positive or negative), ARE pattern and keywords. Users can also specify the size of the upstream/promoter regions (5 to 30 kb) from transcription start site to access the AREs located in those specific regions. Conclusion: ZFARED will be useful in the investigation of the Keap1-Nrf2-ARE pathway and its gene regulation. ZFARED is freely available at http://zfared.buc.edu.in/.

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Mitogenomic analysis of diversity of key whitefly pests in Kenya and its implication to their sustainable management

Scientific Reports ◽

10.1038/s41598-021-85902-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Fathiya M. Khamis ◽

Fidelis L. O. Ombura ◽

Inusa J. Ajene ◽

Komivi S. Akutse ◽

Sevgan Subramanian ◽

...

Keyword(s):

Sustainable Management ◽

Management Strategies ◽

Spatial Models ◽

Abundant Species ◽

Plant Viruses ◽

Pest Species ◽

Agricultural Pests ◽

Protein Coding ◽

Aleyrodes Proletella ◽

Aleurodicus Dispersus

AbstractWhiteflies (Hemiptera: Aleyrodidae) are devastating agricultural pests of economic importance vectoring pathogenic plant viruses. Knowledge on their diversity and distribution in Kenya is scanty, limiting development of effective sustainable management strategies. The present study is aimed at identifying whitefly pest species present in Kenya across different agroecological zones and establish predictive models for the most abundant species in Africa. Whiteflies were sampled in Kenya from key crops known to be severely infested and identified using 16S rRNA markers and complete mitochondrial genomes. Four whitefly species were identified: Aleyrodes proletella, Aleurodicus dispersus, Bemisia afer and Trialeurodesvaporariorum, the latter being the most dominant species across all the agroecology. The assembly of complete mitogenomes and comparative analysis of all 13 protein coding genes confirmed the identities of the four species. Furthermore, prediction spatial models indicated high climatic suitability of T. vaporariorum in Africa, Europe, Central America, parts of Southern America, parts of Australia, New Zealand and Asia. Consequently, our findings provide information to guide biosecurity agencies on protocols to be adopted for precise identification of pest whitefly species in Kenya to serve as an early warning tool against T. vaporariorum invasion into unaffected areas and guide appropriate decision-making on their management.

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Inhibitory Copulation Effect of Vibrational Rival Female Signals of Three Stink Bug Species as a Tool for Mating Disruption

Insects ◽

10.3390/insects12020177 ◽

2021 ◽

Vol 12 (2) ◽

pp. 177

Author(s):

Aline Moreira Dias ◽

Miguel Borges ◽

Maria Carolina Blassioli Moraes ◽

Matheus Lorran Figueira Coelho ◽

Andrej Čokl ◽

...

Keyword(s):

Pest Management ◽

Mating Behavior ◽

Mating Disruption ◽

Management Strategies ◽

Stink Bug ◽

Stink Bugs ◽

Vibratory Communication ◽

Communication Signals ◽

Long Duration ◽

Bean Plants

Stink bugs are major pests in diverse crops around the world. Pest management strategies based on insect behavioral manipulation could help to develop biorational management strategies of stink bugs. Insect mating disruption using vibratory signals is an approach with high potential for pest management. The objective of this work was to investigate the effect of conspecific female rival signals on the mating behavior and copulation of three stink bug species to establish their potential for mating disruption. Previously recorded female rival signals were played back to bean plants where pairs of the Neotropical brown stink bug, Euschistus heros, and two green stink bugs, Chinavia ubica and Chinavia impicticornis were placed. Vibratory communication and mating behavior were recorded for each pair throughout the experimental time (20 min). Female rival signals show a disrupting effect on the reproductive behavior of three conspecific investigated stink bug species. This effect was more clearly expressed in E. heros and C. ubica than in C. impicticornis. The likelihood of copulating in pairs placed on control plants, without rival signals, increased 29.41 times in E. heros, 4.6 times in C. ubica and 1.71 times in C. impicticornis. However, in the last case, the effect of female rivalry signals in copulation was not significant. The effect of mating disruption of female rival signals of the three stink bug species may originate from the observed reduction in specific vibratory communication signals emitted, which influences the duet formation and further development of different phases of mating behavior. Our results suggest that female rival signals have potential for application in manipulation and disruption of mating behavior of stink bugs. Further work needs to focus on the effects of female rival signals used in long duration experiments and also their interactions with chemical communication of stink bugs.

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Histone Modifying Enzymes in Gynaecological Cancers

Cancers ◽

10.3390/cancers13040816 ◽

2021 ◽

Vol 13 (4) ◽

pp. 816

Author(s):

Priya Ramarao-Milne ◽

Olga Kondrashova ◽

Sinead Barry ◽

John D. Hooper ◽

Jason S. Lee ◽

...

Keyword(s):

Genome Instability ◽

Cpg Islands ◽

Gene Promoter ◽

Driver Mutations ◽

Promoter Regions ◽

Post Translational Modifications ◽

Chromatin Dynamics ◽

Cancer Types ◽

Histone Modifying Enzymes

Genetic and epigenetic factors contribute to the development of cancer. Epigenetic dysregulation is common in gynaecological cancers and includes altered methylation at CpG islands in gene promoter regions, global demethylation that leads to genome instability and histone modifications. Histones are a major determinant of chromosomal conformation and stability, and unlike DNA methylation, which is generally associated with gene silencing, are amenable to post-translational modifications that induce facultative chromatin regions, or condensed transcriptionally silent regions that decondense resulting in global alteration of gene expression. In comparison, other components, crucial to the manipulation of chromatin dynamics, such as histone modifying enzymes, are not as well-studied. Inhibitors targeting DNA modifying enzymes, particularly histone modifying enzymes represent a potential cancer treatment. Due to the ability of epigenetic therapies to target multiple pathways simultaneously, tumours with complex mutational landscapes affected by multiple driver mutations may be most amenable to this type of inhibitor. Interrogation of the actionable landscape of different gynaecological cancer types has revealed that some patients have biomarkers which indicate potential sensitivity to epigenetic inhibitors. In this review we describe the role of epigenetics in gynaecological cancers and highlight how it may exploited for treatment.

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“Predator-In-First”: A Preemptive Biological Control Strategy for Sustainable Management of Pepper Pests in Florida

Sustainability ◽

10.3390/su12187816 ◽

2020 ◽

Vol 12 (18) ◽

pp. 7816

Author(s):

Vivek Kumar ◽

Lucky Mehra ◽

Cindy L. McKenzie ◽

Lance S. Osborne

Keyword(s):

Biological Control ◽

Pest Management ◽

Control Strategy ◽

Frankliniella Occidentalis ◽

Management Strategies ◽

Control Program ◽

Field Conditions ◽

High Rate ◽

Polyphagotarsonemus Latus ◽

Consistent Performance

The early establishment of a biocontrol agent in the production system, whether in the greenhouse, nursery, or field, is essential for the success of the biological control program, ensuring growers’ profitability. In an effort to develop a sustainable pest management solution for vegetable growers in Florida, we explored the application of a preemptive biological control strategy, “Predator-In-First” (PIF), in regulating multiple pepper pests, Bemisia tabaci Gennadius, Frankliniella occidentalis Pergande, and Polyphagotarsonemus latus Banks under greenhouse and field conditions during different growing seasons. In these studies, two bell pepper cultivars (7039 and 7141) and the phytoseiid mite Amblyseius swirskii Athias–Henriot were used as a model system. Pepper seedlings (~8 week) of each cultivar were infested with varying rates of A. swirskii (20 or 40 mites/plant or one sachet/10 plant) and allowed to settle on plant hosts for a week before planting in pots or field beds. Results showed a comparative consistent performance of the treatment with the high rate of phytoseiids (40 mites/plant) in regulating B. tabaci and F. occidentalis populations in greenhouse studies, and B. tabaci and P. latus pests under field conditions. During two fall field seasons, higher marketable yields of 12.8% and 20.1% in cultivar 7039, and 24.3% and 39.5% in cultivar 7141 were observed in the treatment with the high rate of phytoseiids compared to the untreated control, indicating yield benefits of the approach. The outcome of the study is encouraging and demonstrates that PIF can be an important tool for organic vegetable growers and a potential alternative to chemical-based conventional pest management strategies. The advantages and limitations of the PIF approach in Florida pepper production are discussed.

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Aggregation Pheromones of Weevils (Coleoptera: Curculionidae): Advances in the Identification and Potential Uses in Semiochemical-Based Pest Management Strategies

Journal of Chemical Ecology ◽

10.1007/s10886-021-01319-1 ◽

2021 ◽

Author(s):

Pamela Taisline Bandeira ◽

Carla Fernanda Fávaro ◽

Wittko Francke ◽

Jan Bergmann ◽

Paulo Henrique Gorgatti Zarbin

Keyword(s):

Pest Management ◽

Management Strategies ◽

Aggregation Pheromones

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Expanding the potential genes of inborn errors of immunity through protein interactions

BMC Genomics ◽

10.1186/s12864-021-07909-3 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Humza A. Khan ◽

Manish J. Butte

Keyword(s):

Genetic Variation ◽

Protein Interactions ◽

Immune Cell ◽

Genetic Disorders ◽

Cell Types ◽

Protein Protein Interactions ◽

Inborn Errors ◽

Post Translational Modifications ◽

New Genes ◽

Inborn Errors Of Immunity

Abstract Background Inborn errors of immunity (IEI) are a group of genetic disorders that impair the immune system, with over 400 genes described so far, and hundreds more to be discovered. To facilitate the search for new genes, we need a way to prioritize among all the genes in the genome those most likely to play an important role in immunity. Results Here we identify a new list of genes by linking known IEI genes to new ones by using open-source databases of protein-protein interactions, post-translational modifications, and transcriptional regulation. We analyze this new set of 2,530 IEI-related genes for their tolerance of genetic variation and by their expression levels in various immune cell types. Conclusions By merging genes derived from protein interactions of known IEI genes with transcriptional data, we offer a new list of candidate genes that may play a role in as-yet undiscovered IEIs.

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