Henry Chung

Michigan State University | MSU · Department of Entomology

Evolutionary changes in traits involved in both ecological divergence and mate choice may produce reproductive isolation and speciation. However, there are few examples of such dual traits, and the genetic and molecular bases of their evolution have not been identified. We show that methyl-branched cuticular hydrocarbons (mbCHCs) are a dual trait t...

Metallothioneins (MTs) are a family of cysteine-rich metal-binding proteins that are important in the chelating and detoxification of toxic heavy metals. Until now, the short length and the low sequence complexity of MTs have hindered the inference of robust phylogenies, hampering the study of their evolution. To address this longstanding question,...

Highly specific expression patterns can be caused by the overlapping activities of activator and repressor sequences in enhancers. However, few studies illuminate how these sequences evolve in the origin of new enhancers. Here, we show that expression of the bond gene in the semicircular wall epithelium (swe) of the Drosophila melanogaster male eja...

Maintaining water balance is a universal challenge for organisms living in terrestrial environments, especially for insects, which have essential roles in our ecosystem. Although the high surface area to volume ratio in insects makes them vulnerable to water loss, insects have evolved different levels of desiccation resistance to adapt to diverse e...

Traits that allow species to survive in extreme environments such as hot-arid deserts have independently evolved in multiple taxa. However, the genetic and evolutionary mechanisms underlying these traits have thus far not been elucidated. Here, we show that Drosophila mojavensis, a desert-adapted fruit fly species, has evolved high desiccation resi...

Tomato plants are susceptible to significant yield losses when infested by the northern root-knot nematode, Meloidogyne hapla. While there are many options for conventional chemical management, few of these options offer effective control for organic growers or those who seek to adopt more environmentally considerate strategies. In this study, we s...

To survive in extreme environments such as hot-arid deserts, desert-dwelling species have evolved physiological traits to withstand the high temperatures and low aridity beyond the physiologically tolerable ranges of most species. Such traits which include reducing water loss have independently evolved in multiple taxa. However, the genetic and evo...

Understanding how endogenous and exogenous factors such as annual seasonal rhythm and photoperiodism affect pesticide toxicity is important to designing integrated pest management strategies. The two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae), a worldwide phytophagous pest species distributed across different zones with con...

Humulus lupulus (commonly known as hop) is an herbaceous plant that is used in brewing throughout the world. Hop cones are an essential ingredient in the production of beer, which makes hops of critical importance to global craft beverage industries. The hop cyst nematode, Heterodera humuli, is a plant-parasitic nematode with the potential to subst...

Maintaining water balance is a universal challenge for organisms living in terrestrial environments, especially for insects, which have essential roles in our ecosystem. Although the high surface area to volume ratio in insects makes them vulnerable to water loss, insects have evolved different levels of desiccation resistance to adapt to diverse e...

Over the last decade, numerous companies have marketed aqueous ozone sprayers for insect and disease management, but little to no data has been published on their efficacy. Thus, we evaluated the potential of both gaseous and aqueous ozone as a potential preharvest insecticide against the adult life stage of the invasive fruit pest, spotted-wing dr...

Mutations with conflicting fitness effects in males and females accumulate in sexual populations, reducing their adaptive capacity.¹,² Although quantitative genetic studies indicate that sexually antagonistic polymorphisms are common,3, 4, 5 their molecular basis and population genetic properties remain poorly understood.⁶,⁷ Here, we show in fruit...

Understanding how endogenous and exogenous factors such as annual seasonal rhythm and photoperiodism affect the toxicity of pesticides can help design integrated pest management strategies. The two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae), a worldwide phytophagous pest species distributed in areas with different time zone...

Plant roots interact with many bacteria, fungi, and microscopic organisms within the soil that can impact how well the plants grow. Some of these microscopic organisms are animals called nematodes, and they are an especially important part of the life in the soil. Nematodes can be good, bad, and neutral for plants. Some scientists called nematologi...

The vinegar fly Drosophila melanogaster is a pivotal model for invertebrate development, genetics, physiology, neuroscience, and disease. The whole family Drosophilidae, which contains over 4,400 species, offers a plethora of cases for comparative and evolutionary studies. Despite a long history of phylogenetic inference, many relationships remain...

Cuticular hydrocarbons (CHCs) are important, multi-function components of the insect epicuticle. In Drosophila spp., CHCs provide protection from desiccation and serve as semiochemicals for both intra- and interspecific communication. We developed a non-lethal method for the modification of Drosophila CHCs profiles through the exposure of live inse...

The vinegar fly Drosophila melanogaster is a pivotal model for invertebrate development, genetics, physiology, neuroscience, and disease. The whole family Drosophilidae, which contains over 4000 species, offers a plethora of cases for comparative and evolutionary studies. Despite a long history of phylogenetic inference, many relationships remain u...

The vinegar fly Drosophila melanogaster is a pivotal model for invertebrate development, genetics, physiology, neuroscience, and disease. The whole family Drosophilidae, which contains over 4000 species, offers a plethora of cases for comparative and evolutionary studies. Despite a long history of phylogenetic inference, many relationships remain u...

Cuticular hydrocarbons (CHCs) are important, multi-function components of the insect epicuticle. In Drosophila spp., CHCs provide protection from desiccation and serve as semiochemicals for both intra- and interspecific communication. We developed a non-lethal method for the modification of Drosophila CHCs profiles through the exposure of live inse...

Cyst nematodes are ranked as the second most damaging plant-parasitic nematode genus of crops worldwide (Jones et al. 2013). The hop cyst nematode, Heterodera humuli, has been reported to cause up to 38% reduction in dry hops per bine (Hay and Pethybridge 2003). America is the top hop producing country worldwide, with 75% of production occurring in...

Well-controlled gene expression is critical for the proper development and function of many traits. Highly-specific temporal and spatial expression patterns are often due to the overlapping activities of activator and repressor sequences that form cis -regulatory elements called enhancers. While many studies have shown that evolutionary changes in...

Metallothioneins (MTs) are a family of cysteine-rich metal-binding proteins that are important in the chelating and detoxification of toxic heavy metals. Until now, the short length and the low sequence complexity of MTs has hindered the possibility of any phylogenetic reconstruction, hampering the study of their evolution. To answer this longstand...

Drosophila pigmentation has been a fruitful model system for understanding the genetic and developmental mechanisms underlying phenotypic evolution. For example, prior work has shown that divergence of the tan gene contributes to pigmentation differences between two members of the virilis group: Drosophila novamexicana, which has a light yellow bod...

Drosophila pigmentation has been a fruitful model system for understanding the genetic and developmental mechanisms underlying phenotypic evolution. For example, prior work has shown that divergence of the tan gene contributes to pigmentation differences between two members of the virilis group: Drosophila novamexicana, which has a light yellow bod...

The interaction of the root lesion nematode Pratylenchus penetrans and the fungal plant pathogen Verticillium dahliae causes potato early die complex (PED) which induces premature vine senescence and dramatically reduces yield in potatoes. Management of PED is often achieved through the use of soil fumigants and nematicides, but their adverse effec...

Heavy metal pollution is becoming an increasingly serious problem in agricultural ecosystems. Heavy metals such as cadmium (Cd) accumulate in the food chain and may lead to detrimental effects on the physiological functions of living organisms, including herbivorous insects. One such example is the Asian Corn Borer, Ostrinia furnacalis (Lepidoptera...

Changes in global temperature and humidity as a result of climate change are producing rapid evolutionary changes in many animal species, including agricultural pests and disease vectors, leading to changes in allele frequencies of genes involved in thermotolerance and desiccation resistance. As some of these genes have pleiotropic effects on insec...

The birth-and-death evolutionary model proposes that some members of a multigene family are phylogenetically stable and persist as a single copy over time whereas other members are phylogenetically unstable and undergo frequent duplication and loss. Functional studies suggest that stable genes are likely to encode essential functions, while rapidly...

Rotations that include winter cover crops are widely used in agricultural systems and can provide numerous agroecological and economic benefits. However, the effects of winter cover crops on arthropod diversity, specifically rice pests and related natural enemies in rice rotation systems, are still largely unknown. We compared the effects of three...

Pheromonal communication is important in insect mate finding and reproduction. Identifying components of pest insect pheromone system is a first step to disrupt pest insect reproduction. In this study, we identified and cloned the pheromone biosynthesis activating neuropeptide receptor (PBANR) from the Asian corn borer, Ostrinia furnacalis (Guenée)...

The birth-and-death evolutionary model proposes that some members of a multigene family are phylogenetically stable and persist as a single copy over time whereas other members are phylogenetically unstable and undergo frequent duplication and loss. Functional studies suggest that stable genes are likely to encode essential functions, while rapidly...

In recent years, research into the chemical ecology of the vinegar fly, Drosophila melanogaster, has yielded a wealth of information on the neural substrates that detect and process pheromones and control behavior. The studies reveal at the cellular and molecular level how behavioral responses to pheromones are initiated and modulated by social, en...

Many of the lipids found on the cuticles of insects function as pheromones and communicate information about age, sex, and reproductive status. In Drosophila, the composition of the information-rich lipid profile is dynamic and changes over the lifetime of an individual. However, the molecular basis of this change is not well understood. To identif...

Expression pattern of oeno-Gal4 and dsx-Gal4 drivers used for screening. Both the oeno-Gal4 (A) and dsx-Gal4 (B) drivers exhibit robust expression in the oenocytes of males and females (arrowheads). The oeno-Gal4 driver also labels the male accessory glands (A; arrowheads) whereas dsx-Gal4 expression is found in the seminal vesicles and ejaculatory...

Sterol and fatty acid supplementation does not rescue female pharate lethality of oeno>spideyRNAi flies. (A) Supplementation with 20-hydroxyecdysone (20HE) or cholesterol; Fisher’s exact test, not significant, N = 16–47. See S6 Table for full genotypes. (B) Supplementation with palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1) or lino...

Fatty acid quantities following spidey knockdown. (A) Levels of total fatty acids (FA) spideyKD female flies were significantly higher than age-matched controls at 7 and 15 days old. (B) Total FA levels in 7 day old spideyKD male flies were higher than in age-matched controls. Differences in FA levels at other ages were not detected. Each data poin...

GCMS quantification of CHC profiles from female transgenic lines. (DOCX)

Full genotypes shown in each figure. (DOCX)

Spidey expression in adult animals. Spidey levels in wildtype Canton-S flies did not significantly differ throughout adulthood (one-way ANOVA, not significant). Expression levels at 7 and 15 days old were normalized to levels at 1 day old. Data represent the mean of 3 experimental replicates ± SEM. Rp49 was used as an internal control for normaliza...

Oeno>spideyRNAi flies exhibiting the Spider-Man “sticky” phenotype adhere to the walls of the vial and cannot be dislodged by vigorous shaking or tapping. (MP4)

RNAi lines used in screen. (DOCX)

DART MS quantification of cuticular lipid profiles from male transgenic lines. (DOCX)

GCMS quantification of CHC profiles from male transgenic lines. (DOCX)

Representative DART MS spectra of transgenic females exhibiting changes in cuticular lipid profiles. (A) Suppression of the desaturase desat1in the oenocytes (red spectrum) resulted in overall lower signal intensity, elevated levels of monoenes relative to dienes and an increase in oxygenated species (arrows) relative to genetic controls (blue spec...

DART MS quantification of cuticular lipid profiles from female transgenic lines. (DOCX)

Dimorphic traits are ubiquitous in nature, but the evolutionary factors leading to dimorphism are largely unclear. We investigate a potential case of sexual mimicry in Drosophila erecta, in which females show contrasting resemblance to males. We map the genetic basis of this sex-limited colour dimorphism to a region containing the gene tan. We find...

Supplementary Figures 1-5, Supplementary Tables 1-2 and Supplementary Notes 1-4

For many species of insects, lipid pheromones profoundly influence survival, reproduction, and social organization. Unravelling the chemical language of insects has been the subject of intense research in the field of chemical ecology for the past five decades. Characterizing the forms, functions, and biosynthesis of lipid pheromones has led not on...

Evolutionary changes in traits that affect both ecological divergence and mating signals could lead to reproductive isolation and the formation of new species. Insect cuticular hydrocarbons (CHCs) are potential examples of such dual traits. They form a waxy layer on the cuticle of the insect to maintain water balance and prevent desiccation, while...

Widespread use of insecticides has led to insecticide resistance in many populations of insects. In some populations, resistance has evolved to multiple pesticides. In Drosophila melanogaster, resistance to multiple classes of insecticide is due to the overexpression of a single cytochrome P450 gene, Cyp6g1. Overexpression of Cyp6g1 appears to have...

The sequencing of numerous insect genomes has revealed dynamic changes in the number and identity of cytochrome P450 genes in different insects. In the evolutionary sense, the rapid birth and death of many P450 genes is observed, with only a small number of P450 genes showing orthology between insects with sequenced genomes. It is likely that these...

Organisms induce the expression of detoxification enzymes such as cytochrome P450s to deal with xenobiotics encountered in the environment. Research using cell culture systems has identified some of the cis-regulatory elements (CREs) and transcription factors involved in the induction of P450 genes in response to xenobiotic challenges. It was recen...

Cytochrome P450s form a large and diverse family of heme-containing proteins capable of carrying out many different enzymatic reactions. In both mammals and plants, some P450s are known to carry out reactions essential for processes such as hormone synthesis, while other P450s are involved in the detoxification of environmental compounds. In genera...

The conserved relationship between orthologs of many cytochrome P450 genes involved in ecdysone synthesis is not reflected in the evolution of the Drosophila Cyp307a genes. In Drosophila melanogaster Cyp307a1 (spook) and Cyp307a2 (spookier) both play essential roles in ecdysone synthesis and may possess biochemically redundant functions. Using phyl...

Transposable elements are a major mutation source and powerful agents of adaptive change. Some transposable element insertions in genomes increase to a high frequency because of the selective advantage the mutant phenotype provides. Cyp6g1-mediated insecticide resistance in Drosophila melanogaster is due to the upregulation of the cytochrome P450 g...

Modifications of metabolic pathways are important in insecticide resistance evolution. Mutations leading to changes in expression levels or substrate specificities of cytochrome P450 (P450), glutathione-S-transferase (GST) and esterase genes have been linked to many cases of resistance with the responsible enzyme shown to utilize the insecticide as...

Lufenuron is an insect growth regulator insecticide mainly used for the control of the cat flea. To understand mechanisms of resistance to lufenuron, we have characterized lufenuron resistance in a natural population of Drosophila melanogaster. In this study we have used precise genetic mapping to identify a mechanism of lufenuron resistance: the o...

We performed sequence analysis of all the exons and exon-intron boundaries in familial and young-onset Parkinson's disease (PD) in an Asian cohort. None of the patients carried any pathogenic mutations in the Nurr1 gene. We demonstrated a 5 to 10% prevalence of the intron 7 +33 C-->T variant among Malay and Indian PD and healthy controls, suggestin...

Few studies have examined the relationship of coffee and tea in Parkinson's disease (PD). The potential protective effect of coffee intake and risk of PD has not been studied in a Chinese population. There is a high prevalence of caffeine takers among Chinese in our population. We undertook a case control study to examine the relationship between c...

Nurr1 gene plays an important role in the development of the mesencephalic dopaminergic system. Genetic variability of Nurr1 gene may be associated with risk of Parkinson's disease (PD). We found three polymorphic loci (c.-2922(C)2-3, IVS6+18insG and EX8+657 (9-10CA)) of the Nurr1 gene in our PD patients and a novel intron 7+33 C-->T variant in one...

Larvae of the genus Chironomus are often able to survive high levels of pollution. This makes,them of value as potential indicators of pollution and for studies of the genetic mechanisms,that permit such survival. Identification of genes that are up-regulated in the presence of pollutants, such as heavy metals, provides the potential to detect incr...