Life Sciences Commons^™

Species Delimitation, Discovery And Conservation In A Tiger Beetle Species Complex Despite Discordant Genetic Data., Daniel P. Duran, Robert A Laroche, Stephen J Roman, William Godwin, David P Herrmann, Ethan Bull, Scott P Egan

School of Earth & Environment Faculty Scholarship

In an age of species declines, delineating and discovering biodiversity is critical for both taxonomic accuracy and conservation. In recent years, there has been a movement away from using exclusively morphological characters to delineate and describe taxa and an increase in the use of molecular markers to describe diversity or through integrative taxonomy, which employs traditional morphological characters, as well as genetic or other data. Tiger beetles are charismatic, of conservation concern, and much work has been done on the morphological delineation of species and subspecies, but few of these taxa have been tested with genetic analyses. In this study, …

Molecular Evolutionary Trends And Feeding Ecology Diversification In The Hemiptera, Anchored By The Milkweed Bug Genome, Kristen A. Panfilio, Iris M. Vargas Jentzsch, Joshua B. Benoit, Deniz Erezyilmaz, Yuichiro Suzuki, Stefano Colella, Hugh M. Robertson, Monica F. Poelchau, Robert M. Waterhouse, Panagiotis Ioannidis, Matthew T. Weirauch, Daniel S. T. Hughes, Shwetha C. Murali, John H. Werren, Chris G. C. Jacobs, Elizabeth J. Duncan, David Armisén, Barbara M. I. Vreede, Patrice Baa-Puyoulet, Chloé S. Berger, Chun-Che Chang, Hsu Chao, Mei-Ju M. Chen, Yen-Ta Chen, Christopher P. Childers, Ariel D. Chipman, Andrew G. Cridge, Antonin J. J. Crumière, Peter K. Dearden, Elise M. Didion, Subba Reddy Palli, Jayendra Nath Shukla

Entomology Faculty Publications

Background: The Hemiptera (aphids, cicadas, and true bugs) are a key insect order, with high diversity for feeding ecology and excellent experimental tractability for molecular genetics. Building upon recent sequencing of hemipteran pests such as phloem-feeding aphids and blood-feeding bed bugs, we present the genome sequence and comparative analyses centered on the milkweed bug Oncopeltus fasciatus, a seed feeder of the family Lygaeidae.

Results: The 926-Mb Oncopeltus genome is well represented by the current assembly and official gene set. We use our genomic and RNA-seq data not only to characterize the protein-coding gene repertoire and perform isoform-specific RNAi, but …

Molecular Gut Content Analysis Of Different Spider Body Parts, Nuria Macías-Hernández, Kacie J. Athey, Vanina Tonzo, Owen S. Wangensteen, Miquel Arnedo, James D Harwood

Entomology Faculty Publications

Molecular gut-content analysis has revolutionized the study of food webs and feeding interactions, allowing the detection of prey DNA within the gut of many organisms. However, successful prey detection is a challenging procedure in which many factors affect every step, starting from the DNA extraction process. Spiders are liquid feeders with branched gut diverticula extending into their legs and throughout the prosoma, thus digestion takes places in different parts of the body and simple gut dissection is not possible. In this study, we investigated differences in prey detectability in DNA extracts from different parts of the spider´s body: legs, prosoma …

Foraging Distance Of The Argentine Ant In California Vineyards., Brian N. Hogg, Erik H. Nelson, James R. Hagler, Kent M. Daane

Natural Sciences and Mathematics | Faculty Scholarship

Argentine ants, Linepithema humile (Mayr) (Hymenoptera: Formicidae), form mutualisms with hemipteran pests in crop systems. In vineyards, they feed on honeydew produced by mealybugs and soft scales, which they tend and protect from natural enemies. Few options for controlling Argentine ants are available; one of the more effective approaches is to use liquid baits containing a low dose of an insecticide. Knowledge of ant foraging patterns is required to estimate how many bait stations to deploy per unit area. To measure how far ants move liquid bait in vineyards, we placed bait stations containing sugar water and a protein marker …

Advancing Behavioural Genomics By Considering Timescale, Clare C. Rittschof, Kimberly A. Hughes

Entomology Faculty Publications

Animal behavioural traits often covary with gene expression, pointing towards a genomic constraint on organismal responses to environmental cues. This pattern highlights a gap in our understanding of the time course of environmentally responsive gene expression, and moreover, how these dynamics are regulated. Advances in behavioural genomics explore how gene expression dynamics are correlated with behavioural traits that range from stable to highly labile. We consider the idea that certain genomic regulatory mechanisms may predict the timescale of an environmental effect on behaviour. This temporally minded approach could inform both organismal and evolutionary questions ranging from the remediation of early …

Creb-Binding Protein Plays Key Roles In Juvenile Hormone Action In The Red Flour Beetle, Tribolium Castaneum, Jingjing Xu, Amit Roy, Subba Reddy Palli

Entomology Faculty Publications

Juvenile hormones (JH) and ecdysteroids regulate many biological and metabolic processes. CREB-binding protein (CBP) is a transcriptional co-regulator with histone acetyltransferase (HAT) activity. Therefore, CBP is involved in activation of many transcription factors that regulate expression of genes associated with postembryonic development in insects. However, the function of CBP in JH action in insects is not well understood. Hence, we studied the role of CBP in JH action in the red flour beetle, Tribolium castaneum and the Tribolium cell line. CBP knockdown caused a decrease in JH induction of genes, Kr-h1, 4EBP and G13402 in T. castaneum larvae, adults and …

Selection Of Housekeeping Genes And Demonstration Of Rnai In Cotton Leafhopper, Amrasca Biguttula Biguttula (Ishida), Satnam Singh, Mridula Gupta, Suneet Pandher, Gurmeet Kaur, Pankaj Rathore, Subba Reddy Palli

Entomology Faculty Publications

Amrasca biguttula biguttula (Ishida) commonly known as cotton leafhopper is a severe pest of cotton and okra. Not much is known on this insect at molecular level due to lack of genomic and transcriptomic data. To prepare for functional genomic studies in this insect, we evaluated 15 common housekeeping genes (Tub, B-Tub, EF alpha, GADPH, UbiCF, RP13, Ubiq, G3PD, VATPase, Actin, 18s, 28s, TATA, ETF, SOD and Cytolytic actin) during different developmental stages and under starvation stress. We selected early (1^st and 2 …

Historical Observations And Identifications Of Plants And Animals In The Vicinity Of Engineer Cantonment In 1819-1820, Hugh H. Genoways, Brett C. Ratcliffe, Carl R. Falk, John R. Bozell

University of Nebraska State Museum: Mammalogy Papers

Historical observations and identifications of plants and animals in the vicinity of Engineer Cantonment in 1819–1820 (James 1822) are shown below in Roman and Roman italic print. Specimens identified through phytoarcheological and zooarcheological analysis of materials and believed to be reasonably associated or contemporaneous with the Long Expedition use of the site (AU4) are shown in boldface. Species present in both the historical and archeological data are marked by an asterisk (*). References used in this compilation include Benedict (1996), Brewer (1970 [1840]), Conant and Collins (1991), Ducey (2000), Evans (1997), Falk et al. (this volume), Genoways et al. (2008), …

Mitochondrial Phylogenomics Of Hemiptera Reveals Adaptive Innovations Driving The Diversification Of True Bugs, Hu Li, John Moeller Leavengood Jr., Eric G. Chapman, Daniel Burkhardt, Fan Song, Pei Jiang, Jinpeng Liu, Xuguo Zhou, Wanzhi Cai

Entomology Faculty Publications

Hemiptera, the largest non-holometabolous order of insects, represents approximately 7% of metazoan diversity. With extraordinary life histories and highly specialized morphological adaptations, hemipterans have exploited diverse habitats and food sources through approximately 300 Myr of evolution. To elucidate the phylogeny and evolutionary history of Hemiptera, we carried out the most comprehensive mitogenomics analysis on the richest taxon sampling to date covering all the suborders and infraorders, including 34 newly sequenced and 94 published mitogenomes. With optimized branch length and sequence heterogeneity, Bayesian analyses using a site-heterogeneous mixture model resolved the higher-level hemipteran phylogeny as (Sternorrhyncha, (Auchenorrhyncha, (Coleorrhyncha, Heteroptera))). Ancestral character …

Phytoplasma Infection Of A Tropical Root Crop Triggers Bottom-Up Cascades By Favoring Generalist Over Specialist Herbivores, Kris A. G. Wyckhuys, Ignazio Graziosi, Dharani Dhar Burra, Abigail Jan Walter

Entomology Faculty Publications

Global interest on plant-microbe-insect interactions is rapidly growing, revealing the multiple ways in which microorganisms mediate plant-herbivore interactions. Phytopathogens regularly alter whole repertoires of plant phenotypic traits, and bring about shifts in key chemical or morphological characteristics of plant hosts. Pathogens can also cause cascading effects on higher trophic levels, and eventually shape entire plant-associated arthropod communities. We tested the hypothesis that a Candidatus Phytoplasma causing cassava witches’ broom (CWB) on cassava (Manihot esculenta Grantz) is altering species composition of invasive herbivores and their associated parasitic hymenopterans. We conducted observational studies in cassava fields in eastern Cambodia to assess …

Life-Shortening Wolbachia Infection Reduces Population Growth Of Aedes Aegypti, Eunho Suh, David R. Mercer, Stephen L. Dobson

Entomology Faculty Publications

Wolbachia bacteria are being introduced into natural populations of vector mosquitoes, with the goal of reducing the transmission of human diseases such as Zika and dengue fever. The successful establishment of Wolbachia infection is largely dependent on the effects of Wolbachia infection to host fitness, but the effects of Wolbachia infection on the individual life-history traits of immature mosquitoes can vary. Here, the effects of life-shortening Wolbachia (wMelPop) on population growth of infected individuals were evaluated by measuring larval survival, developmental time and adult size of Aedes aegypti in intra- (infected or uninfected only) and inter-group (mixed with …

Variation In Dna Methylation Is Not Consistently Reflected By Sociality In Hymenoptera, Karl M. Glastad, Samuel V. Arsenault, Kim L. Vertacnik, Scott M. Geib, Sasha Kay, Bryan N. Danforth, Sandra M. Rehan, Catherine R. Linnen, Sarah D. Kocher, Brendan G. Hunt

Biology Faculty Publications

Changes in gene regulation that underlie phenotypic evolution can be encoded directly in the DNA sequence or mediated by chromatin modifications such as DNA methylation. It has been hypothesized that the evolution of eusocial division of labor is associated with enhanced gene regulatory potential, which may include expansions in DNA methylation in the genomes of Hymenoptera (bees, ants, wasps, and sawflies). Recently, this hypothesis garnered support from analyses of a commonly used metric to estimate DNA methylation in silico, CpG content. Here, we test this hypothesis using direct, nucleotide-level measures of DNA methylation across nine species of Hymenoptera. In doing …

Impact Of Sublethal Exposure To A Pyrethroid-Neonicotinoid Insecticide On Mating, Fecundity And Development In The Bed Bug Cimex Lectularius L. (Hemiptera: Cimicidae), Sydney E. Crawley, Jennifer R. Gordon, Katelyn A. Kowles, Michael F. Potter, Kenneth F. Haynes

Entomology Faculty Publications

Sublethal exposure to an insecticide may alter insect feeding, mating, oviposition, fecundity, development, and many other life history parameters. Such effects may have population-level consequences that are not apparent in traditional dose-mortality evaluations. Earlier, we found that a routinely used combination insecticide that includes a pyrethroid and a neonicotinoid (Temprid^® SC) had deleterious effects on multiple bed bug (Cimex lectularius, L.) behaviors. Here, we demonstrate that sublethal exposure impacts physiology and reproduction as well. We report that sublethal exposure to Temprid SC has variable aberrant effects on bed bugs depending on the strain, including: a reduction in …

Genome-Wide Analysis Of Atp-Binding Cassette (Abc) Transporters In The Sweetpotato Whitefly, Bemisia Tabaci, Lixia Tian, Tianxue Song, Rongjun He, Yang Zeng, Wen Xie, Qingjun Wu, Shaoli Wang, Xuguo Zhou, Youjun Zhang

Entomology Faculty Publications

Background: ABC transporter superfamily is one of the largest and ubiquitous groups of proteins. Because of their role in detoxification, insect ABC transporters have gained more attention in recent years. In this study, we annotated ABC transporters from a newly sequenced sweetpotato whitefly genome. Bemisia tabaci Q biotype is an emerging global invasive species that has caused extensive damages to field crops as well as ornamental plants.

Results: A total of 55 ABC transporters containing all eight described subfamilies (A to H) were identified in the B. tabaci Q genome, including 8 ABCAs, 3 ABCBs, 6 ABCCs, 2 ABCDs, 1 …

Genome Sequencing Of The Sweetpotato Whitefly Bemisia Tabaci Med/Q, Wen Xie, Chunhai Chen, Zezhong Yang, Litao Guo, Xin Yang, Dan Wang, Ming Chen, Jinqun Huang, Yanan Wen, Yang Zeng, Yating Liu, Jixing Xia, Lixia Tian, Hongying Cui, Qingjun Wu, Shaoli Wang, Baoyun Xu, Xianchun Li, Xinqiu Tan, Murad Ghanim, Baoli Qiu, Huipeng Pan, Dong Chu, Helene Delatte, M. N. Maruthi, Feng Ge, Xueping Zhou, Xiaowei Wang, Fanghao Wan, Yuzhou Du, Xuguo Joe Zhou

Entomology Faculty Publications

The sweetpotato whitefly Bemisia tabaci is a highly destructive agricultural and ornamental crop pest. It damages host plants through both phloem feeding and vectoring plant pathogens. Introductions of B. tabaci are difficult to quarantine and eradicate because of its high reproductive rates, broad host plant range, and insecticide resistance. A total of 791 Gb of raw DNA sequence from whole genome shotgun sequencing, and 13 BAC pooling libraries were generated by Illumina sequencing using different combinations of mate-pair and pair-end libraries. Assembly gave a final genome with a scaffold N50 of 437 kb, and a total length of 658 Mb. …

Transcriptomic Response Of Wolf Spider, Pardosa Pseudoannulata, To Transgenic Rice Expressing Bacillus Thuringiensis Cry1ab Protein, Juan Wang, Yuande Peng, Kaifu Xiao, Baoyang Wei, Jilin Hu, Zhi Wang, Qisheng Song, Xuguo Zhou

Entomology Faculty Publications

Background: Bacillum thuringiensis (Bt) toxin produced in Cry1-expressing genetically modified rice (Bt rice) is highly effective to control lepidopteran pests, which reduces the needs for synthetic insecticides. Non-target organisms can be exposed to Bt toxins through direct feeding or trophic interactions in the field. The wolf spider Pardosa pseudoannulata, one of the dominant predators in South China, plays a crucial role in the rice agroecosystem. In this study, we investigated transcriptome responses of the 5th instar spiders fed on preys maintained on Bt- and non-Bt rice.

Results: Comparative transcriptome analysis resulted in 136 differentially expressed genes (DEGs) …

Genome Of The Asian Longhorned Beetle (Anoplophora Glabripennis), A Globally Significant Invasive Species, Reveals Key Functional And Evolutionary Innovations At The Beetle-Plant Interface, Duane D. Mckenna, Erin D. Scully, Yannick Pauchet, Kelli Hoover, Roy Kirsch, Scott M. Geib, Robert F. Mitchell, Robert M. Waterhouse, Seung-Joon Ahn, Deanna Arsala, Joshua B. Benoit, Heath Blackmon, Tiffany Bledsoe, Julia H. Bowsher, André Busch, Bernarda Calla, Hsu Chao, Anna K. Childers, Christopher Childers, Dave J. Clarke, Lorna Cohen, Jeffery P. Demuth, Huyen Dinh, Harshavardhan Doddapaneni, Amanda Dolan, Jian J. Duan, Shannon Dugan, Markus Friedrich, Karl M. Glastad, Michael A. D. Goodisman, Stephanie Haddad, Yi Han, Daniel S. T. Hughes, Panagiotis Ioannidis, J. Spencer Johnston, Jeffery W. Jones, Leslie A. Kuhn, David R. Lance, Chien-Yueh Lee, Sandra L. Lee, Han Lin, Jeremy A. Lynch, Armin P. Moczek, Shwetha C. Murali, Donna M. Muzny, David R. Nelson, Subba R. Palli, Kristen A. Panfilio, Dan Pers, Monica F. Poelchau, Honghu Quan, Jiaxin Qu, Ann M. Ray, Joseph P. Rinehart, Hugh M. Robertson, Richard Roehrdanz, Andrew J. Rosendale, Seunggwan Shin, Christian Silva, Alex S. Torson, Iris M. Vargas Jentzsch, John H. Werren, Kim C. Worley, George Yocum, Evgeny M. Zdobnov, Richard A. Gibbs, Stephen Richards

Entomology Faculty Publications

Background: Relatively little is known about the genomic basis and evolution of wood-feeding in beetles. We undertook genome sequencing and annotation, gene expression assays, studies of plant cell wall degrading enzymes, and other functional and comparative studies of the Asian longhorned beetle, Anoplophora glabripennis, a globally significant invasive species capable of inflicting severe feeding damage on many important tree species. Complementary studies of genes encoding enzymes involved in digestion of woody plant tissues or detoxification of plant allelochemicals were undertaken with the genomes of 14 additional insects, including the newly sequenced emerald ash borer and bull-headed dung beetle.

Results: …

The Salicylic Acid-Mediated Release Of Plant Volatiles Affects The Host Choice Of Bemisia Tabaci, Xiaobin Shi, Gong Chen, Lixia Tian, Zhengke Peng, Wen Xie, Qingjun Wu, Shaoli Wang, Xuguo Zhou, Youjun Zhang

Entomology Faculty Publications

The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) causes serious crop losses worldwide by transmitting viruses. We have previously shown that salicylic acid (SA)-related plant defenses directly affect whiteflies. In this study, we applied exogenous SA to tomato plants in order to investigate the interaction between SA-induced plant volatiles and nonviruliferous B. tabaci B and Q or B- and Q-carrying tomato yellow leaf curl virus (TYLCV). The results showed that exogenous SA caused plants to repel nonviruliferous whiteflies, but the effect was reduced when the SA concentration was low and when the whiteflies were viruliferous. Exogenous SA increased the number and …

20-Hydroxyecdysone (20e) Primary Response Gene E75 Isoforms Mediate Steroidogenesis Autoregulation And Regulate Developmental Timing In Bombyx, Kang Li, Ling Tian, Zhongjian Guo, Sanyou Guo, Jianzhen Zhang, Shi-Hong Gu, Subba Reddy Palli, Yang Cao, Sheng Li

Entomology Faculty Publications

The temporal control mechanisms that precisely control animal development remain largely elusive. The timing of major developmental transitions in insects, including molting and metamorphosis, is coordinated by the steroid hormone 20-hydroxyecdysone (20E). 20E involves feedback loops to maintain pulses of ecdysteroid biosynthesis leading to its upsurge, whereas the underpinning molecular mechanisms are not well understood. Using the silkworm Bombyx mori as a model, we demonstrated that E75, the 20E primary response gene, mediates a regulatory loop between ecdysteroid biosynthesis and 20E signaling. E75 isoforms A and C directly bind to retinoic acid receptor-related response elements in Halloween gene promoter …

Duplication And Remolding Of Trna Genes In The Mitochondrial Genome Of Reduvius Tenebrosus (Hemiptera: Reduviidae), Pei Jiang, Hu Li, Fan Song, Yao Cai, Jianyun Wang, Jinpeng Liu, Wanzhi Cai

Markey Cancer Center Faculty Publications

Most assassin bugs are predators that act as important natural enemies of insect pests. Mitochondrial (mt) genomes of these insects are double-strand circular DNAs that encode 37 genes. In the present study, we explore the duplication and rearrangement of tRNA genes in the mt genome of Reduvius tenebrosus, the first mt genome from the subfamily Reduviinae. The gene order rearranges from CR (control region)-trnI-trnQ-trnM-ND2 to CR-trnQ-trnI2-trnI1-trnM-ND2. We identified 23 tRNA genes, including 22 tRNAs commonly found in insects and an additional trnI (trnI2), which has high sequence similarity to trnM. We found several …

Identification Of Ecdysone Hormone Receptor Agonists As A Therapeutic Approach For Treating Filarial Infections, Amruta S. Mhashilkar, Sai L. Vankayala, Canhui Liu, Fiona Kearns, Priyanka Mehrotra, George Tzertzinis, Subba R. Palli, H. Lee Woodcock, Thomas R. Unnasch

Entomology Faculty Publications

Background A homologue of the ecdysone receptor has previously been identified in human filarial parasites. As the ecdysone receptor is not found in vertebrates, it and the regulatory pathways it controls represent attractive potential chemotherapeutic targets.

Methodology/ Principal Findings Administration of 20-hydroxyecdysone to gerbils infected with B. malayi infective larvae disrupted their development to adult stage parasites. A stable mammalian cell line was created incorporating the B. malayi ecdysone receptor ligand-binding domain, its heterodimer partner and a secreted luciferase reporter in HEK293 cells. This was employed to screen a series of ecdysone agonist, identifying seven agonists active at …

Capturing The Phylogeny Of Holometabola With Mitochondrial Genome Data And Bayesian Site-Heterogeneous Mixture Models, Fan Song, Hu Li, Pei Jiang, Xuguo Zhou, Jinpeng Liu, Changhai Sun, Alfried P. Vogler, Wanzhi Cai

Entomology Faculty Publications

After decades of debate, a mostly satisfactory resolution of relationships among the 11 recognized holometabolan orders of insects has been reached based on nuclear genes, resolving one of the most substantial branches of the tree-of-life, but the relationships are still not well established with mitochondrial genome data. The main reasons have been the absence of sufficient data in several orders and lack of appropriate phylogenetic methods that avoid the systematic errors from compositional and mutational biases in insect mitochondrial genomes. In this study, we assembled the richest taxon sampling of Holometabola to date (199 species in 11 orders), and analyzed …

Aphid Performance Changes With Plant Defense Mediated By Cucumber Mosaic Virus Titer, Xiaobin Shi, Yang Gao, Shuo Yan, Xin Tang, Xuguo Zhou, Deyong Zhang, Yong Liu

Entomology Faculty Publications

Background: Cucumber mosaic virus (CMV) causes appreciable losses in vegetables, ornamentals and agricultural crops. The green peach aphid, Myzus persicae Sulzer (Aphididae) is one of the most efficient vectors for CMV. The transmission ecology of aphid-vectored CMV has been well investigated. However, the detailed description of the dynamic change in the plant-CMV-aphid interaction associated with plant defense and virus epidemics is not well known.

Results: In this report, we investigated the relationship of virus titer with plant defense of salicylic acid (SA) and jasmonic acid (JA) during the different infection time and their interaction with aphids in CMV-infected tobacco plants. …

A Specialist Herbivore Pest Adaptation To Xenobiotics Through Up-Regulation Of Multiple Cytochrome P450s, Fang Zhu, Timothy W. Moural, David R. Nelson, Subba R. Palli

Entomology Faculty Publications

The adaptation of herbivorous insects to their host plants is hypothesized to be intimately associated with their ubiquitous development of resistance to synthetic pesticides. However, not much is known about the mechanisms underlying the relationship between detoxification of plant toxins and synthetic pesticides. To address this knowledge gap, we used specialist pest Colorado potato beetle (CPB) and its host plant, potato, as a model system. Next-generation sequencing (454 pyrosequencing) was performed to reveal the CPB transcriptome. Differential expression patterns of cytochrome P450 complement (CYPome) were analyzed between the susceptible (S) and imidacloprid resistant (R) beetles. We also evaluated the global …

Genome-Wide Transcriptomic And Proteomic Analyses Of Bollworm-Infested Developing Cotton Bolls Revealed The Genes And Pathways Involved In The Insect Pest Defence Mechanism, Saravanan Kumar, Kanakachari Mogilicherla, Dhandapani Gurusamy, Krishan Kumar, Prabhakaran Narayanasamy, Padmalatha Kethireddy Venkata, Amolkumar Solanke, Savita Gamanagatti, Vamadevaiah Hiremath, Ishwarappa S. Katageri, Sadhu Leelavathi, Polumetla Ananda Kumar, Vanga Siva Reddy

Entomology Faculty Publications

Cotton bollworm, Helicoverpa armigera, is a major insect pest that feeds on cotton bolls causing extensive damage leading to crop and productivity loss. In spite of such a major impact, cotton plant response to bollworm infection is yet to be witnessed. In this context, we have studied the genome-wide response of cotton bolls infested with bollworm using transcriptomic and proteomic approaches. Further, we have validated this data using semi-quantitative real-time PCR. Comparative analyses have revealed that 39% of the transcriptome and 35% of the proteome were differentially regulated during bollworm infestation. Around 36% of significantly regulated transcripts and 45% …

20-Hydroxyecdysone (20e) Primary Response Gene E93 Modulates 20e Signaling To Promote Bombyx Larval-Pupal Metamorphosis, Xi Liu, Fangyin Dai, Enen Guo, Kang Li, Li Ma, Ling Tian, Yang Cao, Guozheng Zhang, Subba Reddy Palli, Sheng Li

Entomology Faculty Publications

As revealed in a previous microarray study to identify genes regulated by 20-hydroxyecdysone (20E) and juvenile hormone (JH) in the silkworm, Bombyx mori, E93 expression in the fat body was markedly low prior to the wandering stage but abundant during larval-pupal metamorphosis. Induced by 20E and suppressed by JH, E93 expression follows this developmental profile in multiple silkworm alleles. The reduction of E93 expression by RNAi disrupted 20E signaling and the 20E-induced autophagy, caspase activity, and cell dissociation in the fat body. Reducing E93 expression also decreased the expression of the 20E-induced pupal-specific cuticle protein genes and prevented growth …

Insecticides Promote Viral Outbreaks By Altering Herbivore Competition, Huipeng Pan, Evan L. Preisser, Dong Chu, Shaoli Wang, Qingjun Wu, Yves Carriére, Xuguo Zhou, Youjun Zhang

Entomology Faculty Publications

While the management of biological invasions is often characterized by a series of single-specieg decisions, invasive species exist within larger food webs. These biotic interactions can alter the impact of control/eradication programs and may cause suppression efforts to inadvertently facilitate invasion spread and impact. We document the rapid replacement of the invasive Bemisia Middle East-Asia Minor I (MEAM1) cryptic biotype by the cryptic Mediterranean (MED) biotype throughout China and demonstrate that MED is more tolerant of insecticides and a better vector of tomato yellow leaf curl virus (TYLCV) than MEAMJ. While MEAM1 usually excludes MED under natural conditions, insecticide application …

Population Dynamics Of Empoasca Fabae (Hemiptera: Cicadellidae) In Central Iowa Alfalfa Fields, L. A. Weiser Erlandson, John J. Obrycki

Entomology Faculty Publications

Adults and nymphs of Empoasca fabae Harris (Hemiptera: Cicadellidae) and adults of predatory species in the families Coccinellidae, Anthocoridae, Nabidae, Chrysopidae, and Hemerobiidae were sampled in Iowa alfalfa fields from June to September in 1999 and 2000. The relationship between each predatory taxa and E. fabae was examined using regression analysis. In 2000, all predators were found to be positively correlated with the presence of E. fabae during all periods sampled and most likely contributed to mortality. Orius insidiosus (Say) (Hemiptera: Anthoridae) was the most numerous insect predatory species; population numbers ranged from 0 to 1 and 0.1 to 3.7 …

Stable Reference Gene Selection For Rt-Qpcr Analysis In Nonviruliferous And Viruliferous Frankliniella Occidentalis, Chunxiao Yang, Hui Li, Huipeng Pan, Yabin Ma, Deyong Zhang, Yong Liu, Zhanhong Zhang, Changying Zheng, Dong Chu

Entomology Faculty Publications

Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for measuring and evaluating gene expression during variable biological processes. To facilitate gene expression studies, normalization of genes of interest relative to stable reference genes is crucial. The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), the main vector of tomato spotted wilt virus (TSWV), is a destructive invasive species. In this study, the expression profiles of 11 candidate reference genes from nonviruliferous and viruliferous F. occidentalis were investigated. Five distinct algorithms, geNorm, NormFinder, BestKeeper, the ΔCt method, and RefFinder, were used to determine the performance …

Selection Of Reference Genes For Rt-Qpcr Analysis In The Monarch Butterfly, Danaus Plexippus (L.), A Migrating Bio-Indicator, Huipeng Pan, Xiaowei Yang, Keith Bidne, Richard L. Hellmich, Blair D. Siegfried, Xuguo Zhou

Entomology Faculty Publications

Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a powerful technique to quantify gene expression. To facilitate gene expression study and obtain accurate results, normalization relative to stably expressed reference genes is crucial. The monarch butterfly, Danaus plexippus (L.), is one of the most recognized insect species for its spectacular annual migration across North America. Besides its great voyages, D. plexippus has drawn attention to its role as a bio-indicator, ranging from genetically modified organisms (GMOs) to natural ecosystems. In this study, nine reference genes from D. plexippus genome were selected as the candidate reference genes. The expression profiles of these …