- Author: Kathy Keatley Garvey
A warm welcome!
"UC Davis is a big university, with a strong focus on research," the text begins. "Undergraduates can easily feel like they are lost in the crowd, and rarely get close mentorship from faculty or other research staff (how can you, when your classes have hundreds of students present?). And yet, some of the most important skills for research biologists cannot be taught in big lecture halls or even in lab courses; these skills, especially those linked to conducting cutting-edge research are best learned through close mentoring relationships with faculty, and through an opportunity to do research (try it, make mistakes, learn from those mistakes, and get it right the next time)."
The program, co-founded and co-directed by three faculty members of the UC Davis Department of Entomology and Nematology--distinguished professor Jay Rosenheim and professors Joanna Chiu and Louie Yang--"aims to provide undergraduates with a closely-mentored research experience in biology. Because insects can be used as model systems to explore virtually any area of biology (population biology; behavior and ecology; biodiversity and evolutionary ecology; agroecology; genetics and molecular biology; biochemistry and physiology; cell biology), faculty in the program can provide research opportunities across the full sweep of biology. The program's goal is to provide academically strong and highly motivated undergraduates with a multi-year research experience that cultivates skills that will prepare them for a career in biological research."
From the depths of this innovative and excellent program, launched in 2011, come outstanding scholars--scholars like Gwen Erdosh and Gary Ge, the first two recipients of the Dr. Stephen Garczynski Undergraduate Research Scholarship. This award, sponsored by the Pacific Branch, Entomological Society of America, memorializes Stephen Garczynski (1960-2019), a research geneticist at the USDA Agricultural Research Service in Wapato, Wash.,"who had an unmatched passion for mentoring undergraduate students in their research," according to the PBESA website.
Erdosh, a research scholar in the Yang lab, won the inaugural scholarship, presented in 2022. She's continuing her research, and as @gwentomologist, is sharing her knowledge of entomology with her 77,000 followers on Instagram.
This year Ge won the undergraduate scholarship. He studies with Yang and UC Davis Distinguished Professor Art Shapiro of the Department of Evolution and Ecology, and researches the American Apollo butterfly (Parnassius clodius) as a model to study how microclimatic conditions affect cold-adapted insects. Ge is a research assistant with Shapiro's Central California Butterfly Population and Diversity Trends Study, and works with Yang as a project manager and a research assistant on his Milkweed phenology study.
Ge will be honored at the annual PBESA meeting, April 2-5 in Seattle, which encompasses 11 Western states, plus Canada, Mexico and U.S. territories. He will receive a $1000 award for travel expenses and a waived registration fee.
Ge just finished writing a National Science Foundation's Graduate Research Fellowship Program (GRFP) grant proposal. The results are expected to be announced in April.
His hypothesis: "that mid-elevation populations of P. clodius have the best cold tolerance as overwintering eggs. The main factor behind this is snow cover. Snow cover is known to provide significant insulation to whatever is underneath, usually creating higher microclimatic temperatures under the snow than above. At mid-elevations, the winter temperatures are lower than at low elevations, and the snow cover is supposedly less and more unstable compared to higher elevations. This means the mid-elevation populations are likely exposed to the coldest winter temperature, and have locally adapted to it.”
Ge said he is testing his hypothesis “partly by looking at the supercooling points (SCPs) of diapausing eggs in different populations. The SCP indicates the freezing temperature of the egg, so it should be close to the lower lethal temperature. So, the population with the lowest average SCP would be the most cold-tolerant. I got some preliminary results recently indicating the SCP of the mid-elevation eggs is around -30 °C, which is pretty cold! On the side I am also testing the egg SCP of a Parnassius behrii population. This is a California endemic. It would be cool to see how their thermal tolerance differ from that of P. clodius as P. behrii is only found in high-elevation habitats (mostly around and above 9,000 feet).”
“The genus Parnassius is prone to global warming due to its affinity for alpine and arctic habitats, and several species are considered to be threatened," Ge said.
Shapiro, who has monitored butterfly populations across central California for the last 50 years, says that “Parnassians are a group of cold-adapted Northern Hemisphere butterflies that are becoming increasingly important as objects of physiological, ecological and evolutionary study. They are only likely to grow more important in the context of climate change. Thus, Gary's study is very timely and should attract plenty of attention! It is demanding given the rigorous conditions in which they breed and develop, and he is likely to learn a lot that will facilitate future lab and field studies.” On his research website, Art's Shapiro's Butterfly site, Shapiro describes P. clodius in detail.
Gary, born in Beijing, China, attended elementary school in New York City, middle school in Singapore, and high school in Hawaii, and now California for college. “This allowed me to have experience with a range of lepidopterans and ants and termites as well—social insects are my other favorite group.” He anticipates receiving his bachelor of science degree at UC Davis this year and hopes to enroll in graduate school at UC Davis.
Gary developed his passion for Parnassius during middle school. “When I was visiting my extended family in Tibet, I saw this small white butterfly flying through the seemingly lifeless alpine scree habitat at an elevation of around 1,5000 feet. I later found out that it was a Parnassius species and got immediately intrigued by the fact that they are mostly specialist of alpine and arctic habitats, living in some of the world's coldest and most hostile environments. Since many of the genus members have habitats restricted to mountain tops above the tree line, our P. behrii is an example, climate change--rising tree lines-would leave them nowhere to go. This makes better understanding the ecology of this genus utterly important.”
Congratulations to the scholars, their instructors, and to the UC Davis Research Scholars Program in Insect Biology. And kudos to PBESA for memorializing USDA research geneticist Stephen Garczynski and his "unmatched passion for mentoring undergraduate students in their research."
- Author: Kathy Keatley Garvey
That would include the larvae of Tuta absoluta, a South American tomato leafminer. In its adult stage, it's a moth in the family Gelechilidae. In its larval stage, it's a major agricultural pest.
Since 2008, it has invaded much of Europe, northern Africa, and the Middle East, according to a California Department of Food and Agriculture post.
It hasn't yet invaded the United States, but scientists say it has moved from South America as far north as Costa Rica.
The bug "is a serious and devastating pest of tomatoes, causing crop losses as high as 80 to 100% in areas where it is found," according to a Pest Alert article published by the UC Statewide Integrated Pest Management Program. "This insect bores into leaves, stems, flowers, and fruit, often leaving the fruit unmarketable and altering plant growth structure through destruction of stem apical buds or flower buds. To manage this insect, growers may be forced to greatly increase the number of insecticide applications to their tomato crops."
The article, by UC Davis scientists Kris Godfrey of the Contained Research Facility, and Frank Zalom and Joanna Chiu, both of the Department of Entomology and Nematology, points out that the "South American tomato leafminer spreads via commercial trade of plants and fruit infested with eggs, larvae, and pupae. The adult moths can fly, but it is not known if this movement contributes significantly to its spread. There are numerous regulations in place that should limit the spread of the South American tomato leafminer in imported commercial tomato plants and fruit. However, movement of fruit and plants by private individuals is not as strongly regulated."
Enter Kyle Lewald, a doctoral candidate in the laboratory of UC Davis molecular geneticist/physiologist Joanna Chiu. He will present his exit seminar on "Using Genomic Data to Understand and Prevent the Spread of Tuta absoluta" at 4:10 p.m., Wednesday, Feb. 22 in 122 Briggs and also on Zoom. The Zoom link:
https://ucdavis.zoom.us/j/95882849672.
Chiu, professor and vice chair, UC Davis Department of Entomology and Nematology, will introduce him.
"Tuta absoluta is a serious agricultural pest of tomato plants," Lewald says in his abstract. "While initially discovered in Peru, it has rapidly invaded tomato fields around the world over the past century, causing widespread damage to the industry. The recent affordability of whole genome sequencing of insects opens the door to a wide number of applications to understand and control this pest."
"Using long read sequencing, we produced and annotated a highly contiguous T. absoluta genome assembly," Lewald noted. "Sequencing of individuals collected across many locations in Latin America allowed us to investigate population structure and diversity levels, as well as identify divergence times and possible migration events occurring between regions. Understanding these historical events can be key to predicting and preventing future invasion events. We also used comparative genomics between morphologically similar gelechiid species to develop efficient molecular diagnostics, allowing field researchers and stakeholders to identify Tuta absoluta rapidly to support quarantine and treatment efforts."
Lewald, who holds a bachelor's degree in molecular and cell biology (2016) from UC Berkeley joined the Chiu lab in 2018.
The UC Davis Department of Entomology and Nematology's winter seminars are held on Wednesdays at 4:10 p.m. in 122 Briggs Hall. All are virtual. Urban landscape entomologist Emily Meineke, assistant professor, coordinates the seminars. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.
- Author: Kathy Keatley Garvey
Native to Southeast Asia, it infests soft-skinned fruits such as strawberries, raspberries, cherries, blueberries, blackberries, peaches and grapes. Scientists first detected it in the United States (central coastal region of California) in 2008.
If you attend UC Davis doctoral candidate Christine Tabuloc's exit seminar at 4:10 p.m., Wednesday, Feb. 15--in-person or virtually--you'll get a grasp of the work she's doing involving D. suzukii, a worldwide pest, and D. melanogaster, a common species used worldwide as a model organism in genetics.
Tabuloc, advised by molecular geneticist and physiologist Joanna Chui, professor and vice chair of the UC Davis Department of Entomology and Nematology, will speak on "Environmental and Anthropogenic Impact on Insect Gene Expression and Physiology" in 122 Briggs Hall Her seminar also will be virtual. The Zoom link:
https://ucdavis.zoom.us/j/95882849672.
Professor Chiu will introduce her. A pre-seminar coffee session is set from 3:30 to 4:10 p.m. in Briggs 158.
"Natural environmental factors and anthropogenic disturbances can modulate gene expression, resulting in
alteration of organismal phenotype," Tabuloc says in her abstract. "In the first part of my thesis project, I used Drosophila melanogaster as an insect model to understand the mechanisms by which 24-hour light-dark cycles can regulate rhythmic changes in the chromatin to generate circadian rhythms of gene expression and orchestrate daily biological rhythms. I observed that two clock proteins, CLOCK and TIMELESS, regulate daily rhythmicity in the binding of BRAHMA, a chromatin remodeler, to DNA spanning clock-controlled genes to facilitate their rhythmic gene expression cycles. Moreover, because TIMELESS degrades in the presence of light, my results provide new insights into how light affects DNA structure and gene expression."
"In the second part of my thesis project, I investigated the impact of insecticide applications on the
fruit pest Drosophila suzukii," Tabuloc said. "Specifically, I performed RNA sequencing analysis on D. suzukii flies that are either susceptible or resistant to common insecticides to determine genetic mechanisms underlying insecticide resistance in this agricultural pest. My results revealed that enhanced metabolic detoxification confers pyrethroid resistance while
spinosad resistance is the result of both metabolic and penetration resistance. Finally, we identified alternative splicing
as an additional mechanism of resistance. These results will facilitate the development of efficient molecular
diagnostics to identify insecticide resistance in the field and enable growers to adjust D. suzukii spray programs to
control this devastating pest more effectively."
Christine received her bachelor of science degree in biochemistry and molecular biology from UC Davis in 2015. She joined the Chiu lab as an undergraduate research assistant in 2012. "Much of my work in the lab has involved different agricultural pests and investigating the molecular aspects contributing to the insect's ability to be an effective pest," she says on the Chiu lab website. "My current focus is to investigate the effects of climatic change on gene expression of an invasive pest and determine whether there is a correlation to resistance and survival. In addition to pest management research, I am also studying a kinase of a core clock protein in Drosophila melanogaster and hoping to dissect its functional contribution to the molecular oscillator."
The UC Davis Department of Entomology and Nematology's winter seminars are held on Wednesdays at 4:10 p.m. in 122 Briggs Hall. All are virtual. They are coordinated by urban landscape entomologist Emily Meineke, assistant professor. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.
- Author: Kathy Keatley Garvey
Enter molecular geneticist and mosquito researcher Clément Vinauger, an assistant professor with the Department of Biochemistry, Virginia Polytechnic Institute and State University (aka Virginia Tech), Blacksburg Va., who will present a virtual seminar hosted by the UC Davis Entomology and Nematology on "Neural and Molecular Basis of Mosquito Behavior" on Wednesday, Jan. 11.
His seminar, open to all interested persons, begins at 4:10 p.m. (Pacific Time). The Zoom link: https://ucdavis.zoom.us/j/95882849672.
"Because they vector pathogens to humans, mosquitoes impact millions of people every year," Vinauger says in his abstract. "The global strategy for the management of mosquito-borne diseases involves controlling vector populations, to a large extent, through insecticide application. However, vector-borne diseases are now resurgent, largely because of rising insecticide resistance in vector populations and the drug resistance of pathogens. In this context, the Vinauger Lab studies the molecular, physiological, and neural basis of mosquito behavior. We rely on a collaborative, integrative, and multidisciplinary approach, at the intersection between data science, neuro-ethology, molecular biology, and chemical ecology. Our long-term goal is to identify targets to disrupt mosquito-host interactions and reduce mosquito-borne disease transmission."
Molecular geneticist and physiologist Joanna Chiu, professor and vice chair of the Department of Entomology and Nematology and a Chancellor's Fellow, will serve as the host. "I have very high regard for Dr. Vinauger's integrative and multidisciplinary research into the biochemical and neurophysiological basis of insect behavior," Professor Chiu said. "His research program is innovative and rigorous, leveraging techniques in quantitative behavioral analysis, bioengineering, neurobiology, and computational methods to address exciting and important questions in mosquito biology and behavior."
You may have read about Vinauger's work, including the sleep-deprivation research that he and his lab did. Deprive mosquitoes of their sleep and that "may affect mosquitoes' ability to find human hosts or even stop their ability to spread disease," according to an article published Oct. 5, 2022 by Virginia Tech in announcing that he received a two-year $430,000 grant from the National Institutes of Health "to research the sleep habits of mosquitoes with the thought that if sleep-deprived humans have trouble functioning, maybe sleep-deprived mosquitoes do too."
"Vinauger is collaborating with a team from the University of Cincinnati in this research, the first of its kind to study how sleep deprivation may affect a mosquito's ability to find human hosts or even stop its ability to spread disease," writer Mary Hardbarger related. "A good or bad night's sleep can define a person's day, and the same goes for mosquitoes," she wrote. "In humans, a good night's rest improves memory, immunity health, energy level, and many other functions that contribute to overall well-being."
"Unfortunately, solid sleep is just as helpful to the mission of mosquitoes," she pointed out. "The more sleep they get, the more likely they are to buzz, bite, and spread disease. Fortunately, though, sleep-deprived mosquitoes are just as miserable as the sleep-deprived humans they hunt."
The Vinauger lab's latest publication, "Visual Threats Reduce Blood-Feeding and Trigger Escape Responses in Aedes aegypti Mosquitoes," appears in the Dec. 9, 2022 edition of Scientific Reports.
Jason Bittel of the Washington Post wrote about Vinauger's work in a Kids' Post, "Ever Wonder How Mosquitoes Find You?" published Aug. 5, 2019.
"Mosquitoes don't just use one sense to look for dinner," Bittel wrote. "They have evolved a sort of Swiss Army knife of tools that tells them when fresh blood is close by."
Vinauger told him: “The first thing is that they smell us."
Thinking outside the box, Vinaguer and his lab created tiny plastic helmets for the mosquitoes and gathered images from the brain into how they think.
"...when a mosquito gets a whiff of carbon dioxide, the smelling part of its brain begins to send messages to the visual part telling it to be on the lookout for food," Bittel wrote.
Apparently, a whiff and you're it, you're the food.
Vinauger joined the Virginia Tech faculty in October 2017, after serving as a postdoctoral research associate at the University of Washington, Seattle. Educated in France, earning three degrees there, he received his bachelor of science degree in biology/biological sciences in 2006 from the University of Orléans; his master's degree in 2008 from the University of Tours; and his doctorate in 2011 from the University of Tours, Research Institute on Insect Biology.
Vinauger's seminar is the first in a series of winter seminars hosted by the UC Davis Department of Entomology seminars on Wednesdays through March 15. (See schedule.) Eight of the 10 will be in-person in 122 Briggs Hall, and all will be virtual.
- Author: Kathy Keatley Garvey
That was molecular geneticist Yao Cai, entertaining with several other members of the UC Davis Entomology Graduate Student Association (EGSA). He was dressed--quite appropriately, too--as a fruit fly, Drosophila melanogaster, which he described as “our favorite model organism in Insecta!” (See Bug Squad blog.)
Entomology Today, a publication of the Entomological Society of America, picked up the story, headlining it as "Bugs and Beats."
Now fast forward...past the two-year pandemic...and way over to 2022. Time flies, right?
Cai now holds a doctorate in entomology (as of September) and will present his exit seminar, "How Do Flies Tell the Time of Day?" at the next UC Davis Department of Entomology and Nematology seminar, set Wednesday, Oct. 26.
He will deliver his seminar both in-person and virtually at 4:10 p.m. in 122 Briggs Hall. The Zoom link:
https://ucdavis.zoom.us/j/95882849672.
Cai will be introduced by his major professor, molecular geneticist and physiologist Joanna Chiu, professor and vice chair of the department.
"This study highlights the importance of post-translational regulation of circadian rhythms," Cao noted. "Finally, together with previous studies in fungi and mammals, our results suggest a conserved feature in eukaryotic clocks by which transcriptional repressors recruit CK1s to modulate the activity of transcription activators."
A native of southeast Asia, Cai holds two degrees from China Agricultural University, Beijing: a bachelor of science degree (2014) in plant protection and a master's degree in entomology (2016).
What sparked his interest in entomology? "The insect world presented to me the diversity of species when I was a kid," he related. "Since then, I have wondered about the origin and evolution of species. I was lucky to cultivate my interest as an undergrad and then a master student in Chinese Agricultural University. As a PhD student in the Department of Entomology andNematology at UC Davis, this interest expanded to the cellular and molecular mechanisms of evolution and adaptation. Upon my graduation in summer 2022, I continued my postdoctoral research in the Chiu lab. I hope this will prepare me to become a professor in biological sciences."
Cai completed an International Chronobiology Summer School (virtual) in 2020 and a UC Davis Comprehensive Course in Flow Cytometry in 2019. His publications include:
- Cai YD*, Joshi R*, Xia Y, Chiu JC, Emery P (2022) PERIOD phosphoclusters control temperature compensation of the Drosophila circadian clock, Frontiers in Physiology. 13: 888262.
- Cai YD, Sotelo SH, Jackson K, Chiu JC (2022) Assaying circadian locomotor activity rhythm in Drosophila, in “Circadian Rhythms” in NeuroMethods series. ed. M. Hatori, T. Hirota, and S. Panda. Springer Nature, Switzerland.
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Cai Y.D., Y. Xue, C. Truong, J. Del-Carmen Li, C. Ochoa, J.T. Vanselow, K.A. Murphy, Y.H. Li, X. Liu, B.L. Kunimoto, H. Zheng, C. Zhao, Y. Zhang, A. Schlosser, J.C. Chiu (2021). CK2 inhibits TIMELESS nuclear export and modulates CLOCK transcriptional activity to regulate circadian rhythms. Current Biology 31(3): 502-514.
- Cai, Y.D., J.C. Chiu (2021). Timeless in animal circadian clocks and beyond. FEBS Journal (Online ahead of print). doi: 10.1111/febs.16253.
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Abrieux, A., Y. Xue, Y. Cai, K.M. Lewald, H.N. Nguyen, Y. Zhang, J.C. Chiu. (2020). EYES ABSENT and TIMELESS integrate photoperiodic and temperature cues to regulate seasonal physiology in Drosophila. Proceedings of the National Academy of Sciences. U.S.A. 117(26): 15293-15304.
Active in academics, Cai served as a guest lecturer for Entomology 102 on the "Insect Nervous System" and for Entomology 10 on "Insect Circadian Rhythm." He also served as a teaching assistant for a number of UC Davis classes, including Applications, Values, and Ethics in Animal Research; Insect Physiology; Introduction to Biology: Ecology and Evolution; Introduction to Biology: Cell Functions; and Calculus for Biology and Medicine. In addition, he has assisted at Bohart Museum of Entomology open houses and at science program provided by Peregrine School, Davis.
Honored with a number of awards, Cai received a 2021 Chinese Government Award for Outstanding Self-Finance Students Abroad; a 2021 UC Davis Entomology W. Harry Lange, Jr. Memorial Travel Fund; 2021 UC Davis Marv Kinsey Scholarship; a 2020 Boroughs Welcome Fund Society for Research on Biological Rhythms (SRBR) Excellence Award; a 2020 UC Davis Sean and Anne Duffey and Hugh and Geraldine Dingle Research Fellowship; a 2019 UC Davis McBeth Memorial Scholarship; and a 2018 and 2017 UC Davis Henry A. Jastro Graduate Research Awards, among others.
Emily Meineke, assistant professor of urban landscape entomology, UC Davis Department of Entomology and Nematology, coordinates the department's seminars for the 2022-23 academic year. All 11 seminars will take place both person and virtually at 4:10 p.m. on Wednesdays in Room 122 of Briggs Hall except for the Nov. 9th and Dec. 7th seminars, which will be virtual only, she said. (See list of seminars)
For further information on the seminars or to resolve any technical difficulties with Zoom, contact Meineke at ekmeineke@ucdavis.edu.