Genetics and Genomics Commons^™

Multiple Functions Of Creb-Binding Protein During Postembryonic Development: Identification Of Target Genes, Amit Roy, Smitha George, Subba Reddy Palli

Entomology Faculty Publications

Background: Juvenile hormones (JH) and ecdysteroids control postembryonic development in insects. They serve as valuable targets for pest management. Hence, understanding the molecular mechanisms of their action is of crucial importance. CREB-binding protein (CBP) is a universal transcriptional co-regulator. It controls the expression of several genes including those from hormone signaling pathways through co-activation of many transcription factors. However, the role of CBP during postembryonic development in insects is not well understood. Therefore, we have studied the role of CBP in postembryonic development in Tribolium, a model coleopteran insect.

Results: CBP is ubiquitously expressed in the red flour beetle, …

Revision Of The Species Of Lytopylus From Area De Conservación Guanacaste, Northwestern Costa Rica (Hymenoptera, Braconidae, Agathidinae), Ilgoo Kang, Eric G. Chapman, Daniel H. Janzen, Winnie Hallwachs, Tanya Dapkey, M. Alex Smith, Michael J. Sharkey

Entomology Faculty Publications

Thirty two new species of Lytopylus (Agathidinae) are described with image plates for each species: Lytopylus alejandromasisi sp. n., Lytopylus alfredomainieri sp. n., Lytopylusanamariamongeae sp. n., Lytopylus angelagonzalezae sp. n., Lytopylus cesarmorai sp. n., Lytopylus eddysanchezi sp. n., Lytopylus eliethcantillanoae sp. n., Lytopylus ericchapmani sp. n., Lytopylus gahyunae sp. n., Lytopylus gisukae sp. n., Lytopylus guillermopereirai sp. n., Lytopylusgustavoindunii sp. n., Lytopylus hartmanguidoi sp. n., Lytopylus hernanbravoi sp. n., Lytopylushokwoni sp. n., Lytopylus ivanniasandovalae sp. n., Lytopylus johanvalerioi sp. n., Lytopylusjosecortesi sp. n. …

Characterizing Mekk1: Candidate Behavioural Isolation Gene, Caryn Dooner

Electronic Thesis and Dissertation Repository

Behavioural isolation can occur due to divergence in aspects of courtship and mating, and can contribute to reproductive isolation. The purpose of this study is to determine how a gene, Mekk1, contributes to female rejection behaviour between D. melanogaster and D. simulans. Unique polymorphisms were identified within D. simulans Mekk1 that could contribute to behaviour, most of which are non-coding. Both transcripts of Mekk1 appear to be expressed at similar levels in D. simulans and D. melanogaster. These data also indicate that Mekk1 may be expressed in a specific region of the brain called the mushroom body, …

Characterization Of Plant-Spider Mite Interactions And Establishment Of Tools For Spider Mite Functional Genetic Studies, Nicolas Bensoussan

Electronic Thesis and Dissertation Repository

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most polyphagous herbivores feeding on cell contents of over 1100 plant species including more than 150 crops. However, despite its important pest status and a growing understanding of the molecular basis of its interactions with plant hosts, knowledge of the way mites interface with the plant while feeding and the plant damage directly inflicted by mites is lacking. Likewise, while the use of the reverse genetic tools in plants facilitated our understanding of the establishment of defense mechanisms against spider mite herbivory, such tools are lacking for …

Temporal Transcriptomic Profiling Of The Ant-Feeding Assassin Bug Acanthaspis Cincticrus Reveals A Biased Expression Of Genes Associated With Predation In Nymphs, Fei Kou, Hu Li, Shujuan Li, Huaizhu Xun, Yinqiao Zhang, Ziqiang Sun, Xuguo Zhou, Wanzhi Cai

Entomology Faculty Publications

Acanthaspis cincticrus (Stål) is an assassin bug with a specialized camouflaging behavior to ambush ants in the nymphal stages. In this study, we comprehensively sequenced all the life stages of A. cincticrus, including the eggs, five nymph instars, female and male adults using Illumina HiSeq technology. We obtained 176 million clean sequence reads. The assembled 84,055 unigenes were annotated and classified functionally based on protein databases. Among the unigenes, 29.03% were annotated by one or more databases, suggesting their well-conserved functions. Comparison of the gene expression profiles in the egg, nymph and adult stages revealed certain bias. Functional enrichment …

Field Evidence Challenges The Often-Presumed Relationship Between Early Male Maturation And Female-Biased Sexual Size Dimorphism, Marie Claire Chelini, Eileen Hebets

Eileen Hebets Publications

Female-biased sexual size dimorphism (SSD) is often considered an epiphenomenon of selection for the increased mating opportunities provided by early male maturation (i.e., protandry). Empirical evidence of the adaptive significance of protandry remains nonetheless fairly scarce. We use field data collected throughout the reproductive season of an SSD crab spider, Mecaphesa celer, to test two hypotheses: Protandry provides fitness benefits to males, leading to female-biased SSD, or protandry is an indirect consequence of selection for small male size/large female size. Using field-collected data, we modeled the probability of mating success for females and males according to their timing of …

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 …

Rna Interference In The Asian Longhorned Beetle: Identification Of Key Rnai Genes And Reference Genes For Rt-Qpcr, Thais B. Rodrigues, Ramesh Kumar Dhandapani, Jian J. Duan, Subba Reddy Palli

Entomology Faculty Publications

Asian Longhorned Beetle (ALB) Anoplophora glabripennis is a serious invasive forest pest in several countries including the United States, Canada, and Europe. RNA interference (RNAi) technology is being developed as a novel method for pest management. Here, we identified the ALB core RNAi genes including those coding for Dicer, Argonaute, and double-stranded RNA-binding proteins (dsRBP) as well as for proteins involved in dsRNA transport and the systemic RNAi. We also compared expression of six potential reference genes that could be used to normalize gene expression and selected gapdh and rpl32 as the most reliable genes among different tissues and stages …

Development Of Rnai Method For Screening Candidate Genes To Control Emerald Ash Borer, Agrilus Planipennis, Thais B. Rodrigues, Lynne K. Rieske, Jian J. Duan, Kanakachari Mogilicherla, Subba Reddy Palli

Entomology Faculty Publications

The ingestion of double-strand RNAs (dsRNA) targeting essential genes in an insect could cause mortality. Based on this principle, a new generation of insect control methods using RNA interference (RNAi) are being developed. In this work, we developed a bioassay for oral delivery of dsRNA to an invasive forest and urban tree pest, the emerald ash borer (EAB, Agrilus planipennis). EAB feeds and develops beneath the bark, killing trees rapidly. This behavior, coupled with the lack of a reliable artificial diet for rearing larvae and adults, make them difficult to study. We found that dsRNA is transported and processed …

Swainsonine Biosynthesis Genes In Diverse Symbiotic And Pathogenic Fungi, Daniel Cook, Bruno G. G. Donzelli, Rebecca Creamer, Deana L. Baucom, Dale R. Gardner, Juan Pan, Neil Moore, Stuart B. Krasnoff, Jerzy W. Jaromczyk, Christopher L. Schardl

Plant Pathology Faculty Publications

Swainsonine—a cytotoxic fungal alkaloid and a potential cancer therapy drug—is produced by the insect pathogen and plant symbiont Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glory symbiont belonging to order Chaetothyriales. Genome sequence analyses revealed that these fungi share orthologous gene clusters, designated “SWN,” which included a multifunctional swnKgene comprising predicted adenylylation and acyltransferase domains with their associated thiolation domains, a β-ketoacyl synthase domain, and two reductase domains. The role of swnK was demonstrated by inactivating it in M. robertsii through homologous …

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 …

Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot

Electronic Thesis and Dissertation Repository

Despite the use of the host for dispersal by most parasite species, the extremely loose relationship typical between highly mobile hosts and generalist ectoparasites may lead to very different gene flow patterns between the two, leading in turn to different spatial genetic structure, and potentially different demographic history. I examined how similar gene flow patterns are between Cimex adjunctus, a generalist ectoparasite of bats present throughout North America, and two of its key bat hosts. I first analyzed the continent-scale genetic structure and demographic history of C. adjunctus and compared it to that of two of its hosts, the …

The Foxo Transcription Factor Controls Insect Growth And Development By Regulating Juvenile Hormone Degradation In The Silkworm, Bombyx Mori, Baosheng Zeng, Yuping Huang, Jun Xu, Takahiro Shiotsuki, Hua Bai, Subba Reddy Palli, Yongping Huang, Anjiang Tan

Entomology Faculty Publications

Forkhead box O (FOXO) functions as the terminal transcription factor of the insulin signaling pathway and regulates multiple physiological processes in many organisms, including lifespan in insects. However, how FOXO interacts with hormone signaling to modulate insect growth and development is largely unknown. Here, using the transgene-based CRISPR/Cas9 system, we generated and characterized mutants of the silkworm Bombyx mori FOXO (BmFOXO) to elucidate its physiological functions during development of this lepidopteran insect. The BmFOXO mutant (FOXO-M) exhibited growth delays from the first larval stage and showed precocious metamorphosis, pupating at the end of the fourth instar (trimolter) rather …

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 …

Development Of Site Fidelity In The Nocturnal Amblypygid, Phrynus Marginemaculatus, Jacob M. Graving, Verner P. Bingman, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Amblypygids are capable of navigation in the complex terrain of rainforests in near complete darkness. Path integration is unnecessary for successful homing, and the alternative mechanisms by which they navigate have yet to be elucidated. Here, our aims were to determine whether the amblypygid Phrynus marginemaculatus could be trained to reliably return to a target shelter in a laboratory arena—indicating goal recognition—and to document changes in behavior associated with the development of fidelity. We recorded nocturnal movements and space use by individuals over five nights in an arena in which subjects were provided with two shelters that differed in quality. …

Development Of Near-Isogenic Lines In A Parthenogenetically Reproduced Thrips Species, Frankliniella Occidentalis, Guangdi Yuan, Yanran Wan, Xiaoyu Li, Bingqing He, Youjun Zhang, Baoyun Xu, Shaoli Wang, Wen Xie, Xuguo Zhou, Qingjun Wu

Entomology Faculty Publications

Although near-isogenic lines (NILs) can standardize genetic backgrounds among individuals, it has never been applied in parthenogenetically reproduced animals. Here, through multiple rounds of backcrossing and spinosad screening, we generated spinosad resistant NILs in the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), with a haplo-diploid reproduction system. The resultant F. occidentalis NIL-R strain maintained a resistance ratio over 30,000-fold, which was comparable to its parental resistant strain, Spin-R. More importantly, F. occidentalis NIL-R shared 98.90% genetic similarity with its susceptible parental strain Ivf03. By developing this toolset, we are able to segregate individual resistance and facilitate the mechanistic study …

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. …

Genome Editing Of Wnt-1, A Gene Associated With Segmentation, Via Crispr/Cas9 In The Pine Caterpillar Moth, Dendrolimus Punctatus, Huihui Liu, Qun Liu, Xuguo Zhou, Yongping Huang, Zhen Zhang

Entomology Faculty Publications

The pine caterpillar moth, Dendrolimus punctatus, is a devastating forest pest. Genetic manipulation of this insect pest is limited due to the lack of genomic and functional genomic toolsets. Recently, CRISPR/Cas9 technology has been demonstrated to be a promising approach to modify the genome. To investigate gene functions during the embryogenesis, we introduced CRISPR/Cas9 system in D. punctatus to precisely and effectively manipulate gene expressions inmutant embryos. Compared to controls, knocking out of DpWnt-1, a gene well known for its role in the early body planning, led to high embryonic mortality. Among these mutants, 32.9% of the embryos …

Increased Insertion Number Leads To Increased Sperm Transfer And Fertilization Success In A Nursery Web Spider, Alissa G. Anderson, Eileen Hebets

Eileen Hebets Publications

Across animals, a male's fitness is largely dictated by his ability to fertilize eggs; and there exists a plethora of male adaptations associated with increasing fertilization success. In the nursery web spider, Pisaurina mira, males restrain females prior to and during copulation by wrapping them with silk. Previous research demonstrates that copulatory silk wrapping reduces a male's chance of being sexually cannibalized and increases the number of sperm transfer opportunities (termed insertions) that a male can achieve within a mating. While avoiding cannibalism provides an obvious survival benefit to males, the impact of insertion number on male fitness remains …

Evaluation Of Smartstax And Smartstax Pro Maize Against Western Corn Rootworm And Northern Corn Rootworm: Efficacy And Resistance Management, Graham P. Head, Matthew W. Carroll, Sean P. Evans, Dwain M. Rule, Alan R. Willse, Thomas L. Clark, Nicholas P. Storer, Ronald D. Flannagan, Luke W. Samuel, Lance Meinke

Department of Entomology: Faculty Publications

Background: Cases of western corn rootworm (WCR) field-evolved resistance to Cry3Bb1 and other corn rootworm (CRW) control traits have been reported. Pyramid products expressing multiple CRW traits can delay resistance compared to single trait products. We used field studies to assess the pyramid CRW corn products, SmartStax (expressing Cry3Bb1 and Cry34Ab1/Cry35Ab1) and SmartStax PRO (expressing Cry3Bb1, Cry34Ab1/Cry35Ab1 and DvSnf7), at locations with high WCR densities and possible Cry3Bb1 resistance, and to assess the reduction in adult emergence attributable to DvSnf7 and other traits. Insect resistance models were used to assess durability of SmartStax and SmartStax PRO to WCR resistance.

Results: …

Record Breaking Achievements By Spiders And The Scientists Who Study Them, Stefano Mammola, Peter Michalik, Eileen Hebets, Marco Isaia

Eileen Hebets Publications

Organismal biology has been steadily losing fashion in both formal education and scientific research. Simultaneous with this is an observable decrease in the connection between humans, their environment, and the organisms with which they share the planet. Nonetheless, we propose that organismal biology can facilitate scientific observation, discovery, research, and engagement, especially when the organisms of focus are ubiquitous and charismatic animals such as spiders. Despite being often feared, spiders are mysterious and intriguing, offering a useful foundation for the effective teaching and learning of scientific concepts and processes. In order to provide an entryway for teachers and students—as well …

Importance Of The Antenniform Legs, But Not Vision, For Homing By The Neotropical Whip Spider Paraphrynus Laevifrons, Verner P. Bingman, Jacob M. Graving, Eileen Hebets, Daniel D. Wiegmann

Eileen Hebets Publications

Amblypygids, or whip spiders, are nocturnal, predatory arthropods that display a robust ability to navigate to their home refuge. Prior field observations and displacement studies in amblypygids demonstrated an ability to home from distances as far away as 10 m. In the current study, micro-transmitters were used to take morning position fixes of individual Paraphrynus laevifrons following an experimental displacement of 10 m from their home refuge. The intention was to assess the relative importance of vision compared with sensory input acquired from the antenniform legs for navigation as well as other aspects of their spatial behavior. Displaced individuals were …