Life Sciences Commons^™

Juvenile Hormone Regulates Vitellogenin Gene Expression Through Insulin-Like Peptide Signaling Pathway In The Red Flour Beetle, Tribolium Castaneum, Zhentao Sheng, Jingjing Xu, Hua Bai, Fang Zhu, Subba R. Palli

Entomology Faculty Publications

Our recent studies identified juvenile hormone (JH) and nutrition as the two key signals that regulate vitellogenin (Vg) gene expression in the red flour beetle, Tribolium castaneum. Juvenile hormone regulation of Vg synthesis has been known for a long time in several insects, but the mechanism of JH action is not known. Experiments were conducted to determine the mechanism of action of these two signals in regulation of Vg gene expression. Injection of bovine insulin or FOXO double-stranded RNA into the previtellogenic, starved, or JH-deficient female adults increased Vg mRNA and protein levels, thereby implicating the pivotal role for …

Wolbachia Infections That Reduce Immature Insect Survival: Predicted Impacts On Population Replacement, Philip R. Crain, James W. Mains, Eunho Suh, Yunxin Huang, Philip H. Crowley, Stephen L. Dobson

Entomology Faculty Publications

BACKGROUND: The evolutionary success of Wolbachia bacteria, infections of which are widespread in invertebrates, is largely attributed to an ability to manipulate host reproduction without imposing substantial fitness costs. Here, we describe a stage-structured model with deterministic immature lifestages and a stochastic adult female lifestage. Simulations were conducted to better understand Wolbachia invasions into uninfected host populations. The model includes conventional Wolbachia parameters (the level of cytoplasmic incompatibility, maternal inheritance, the relative fecundity of infected females, and the initial Wolbachia infection frequency) and a new parameter termed relative larval viability (RLV), which is the survival of infected larvae relative to …

Male Mating Competitiveness Of A Wolbachia-Introgressed Aedes Polynesiensis Strain Under Semi-Field Conditions, Eric W. Chambers, Limb Hapairai, Bethany A. Peel, Hervé Bossin, Stephen L. Dobson

Entomology Faculty Publications

BACKGROUND: Lymphatic filariasis (LF), a global public health problem affecting approximately 120 million people worldwide, is a leading cause of disability in the developing world including the South Pacific. Despite decades of ongoing mass drug administration (MDA) in the region, some island nations have not yet achieved the threshold levels of microfilaremia established by the World Health Organization for eliminating transmission. Previously, the generation of a novel Aedes polynesiensis strain (CP) infected with an exogenous type of Wolbachia has been described. The CP mosquito is cytoplasmically incompatible (i.e., effectively sterile) when mated with wildtype mosquitoes, and a strategy was proposed …

Large-Scale Rnai Screen Of G Protein-Coupled Receptors Involved In Larval Growth, Molting And Metamorphosis In The Red Flour Beetle, Hua Bai, Fang Zhu, Kapil Shah, Subba R. Palli

Entomology Faculty Publications

BACKGROUND: The G protein-coupled receptors (GPCRs) belong to the largest superfamily of integral cell membrane proteins and play crucial roles in physiological processes including behavior, development and reproduction. Because of their broad and diverse roles in cellular signaling, GPCRs are the therapeutic targets for many prescription drugs. However, there is no commercial pesticide targeting insect GPCRs. In this study, we employed functional genomics methods and used the red flour beetle, Tribolium castaneum, as a model system to study the physiological roles of GPCRs during the larval growth, molting and metamorphosis.

RESULTS: A total of 111 non-sensory GPCRs were identified in …

Episodic Radiations In The Fly Tree Of Life, Brian M. Wiegmann, Michelle D. Trautwein, Isaac S. Winkler, Norman B. Barr, Jung-Wook Kim, Christine Lambkin, Matthew Bertone, Brian Cassel, Keith Bayless, Alysha Heimberg

Dartmouth Scholarship

Flies are one of four superradiations of insects (along with beetles, wasps, and moths) that account for the majority of animal life on Earth. Diptera includes species known for their ubiquity (Musca domestica house fly), their role as pests (Anopheles gambiae malaria mosquito), and their value as model organisms across the biological sciences (Drosophila melanogaster). A resolved phylogeny for flies provides a framework for genomic, developmental, and evolutionary studies by facilitating comparisons across model organisms, yet recent research has suggested that fly relationships have been obscured by multiple episodes of rapid diversification. We provide a phylogenomic …