- Author: Kathy Keatley Garvey
Green Hall memorializes two outstanding scientists--Mel, a geneticist, and wife Kathleen, a biologist.
Melvin Green, who died Oct. 24, 2017 at age 101, was a UC Davis distinguished professor emeritus of molecular and cellular biology who co-founded the UC Davis Genetics Department (now part of the Department of Molecular and Cellular Biology). Kathleen, who died in 2002, was a UC Davis biologist and a longtime Davis City Council member--she was the first woman elected to serve on the council. A scholarship in her name honors women in science.
Selected the 1971 Davis Citizen of the Year, Kathleen served the community in a number of capacities, including charter member and president of the League of Women Voters in Davis, and a member of the the Sutter Davis Hospital Board of Directors.
Brilliant Scientist
During Mel Green's 60-year career, he was inducted into the National Academy of Sciences and received two Guggenheim fellowships. He inspired generations of students, faculty and staff.
We never met Kathleen, but we knew Mel as a brilliant scientist and a wonderful conversationalist, with a finely honed sense of humor. He was a frequent visitor in the halls and offices of the Department of Entomology and Nematology.
Leal and dozens of colleagues spearheaded a movement among the faculty to rename the building. UC Davis Chancellor Gary May approved the name.
"Not many know that Mel, who grew up in the Depression in a Jewish ghetto, became not only a first-generation college graduate in his family but also the first Jewish person to receive a Ph.D. in zoology and biochemistry from the University of Minnesota (1942)," Leal related. "Mel served in the U. S. Army during World War II, and then joined the UC Davis faculty in 1950. He worked until his nineties. During his lengthy and productive career, he made seminal discoveries concerning the nature of mutations using the fruit fly, Drosophila melanogaster. In particular, Mel is known for his discovery of mobile DNA elements."
"Mel would stop by my office on a regular basis just to check on me, talk science, and sometimes to tell a nice joke. For example, in October 2004 he showed up early in the morning and told me: 'Walter, you are screwed!' I asked why and he told me 'Richard Axel and Linda Buck just got the Nobel Prize for their work on olfaction.' I had a good laugh.'"
Mel connected widely and often with UC Davis entomologists, including Bruce Hammock, Hugh Dingle, Lynn Kimsey and Robert Kimsey. Lynn, director of the Bohart Museum of Entomology and a professor of entomology, identified the insect taxonomy for Mel's article, "It Really Is Not a Fruit Fly," appearing in the Sept. 1, 2002 edition of the journal Genetics.
In the article, Green pointed out that the genus Drosophila includes more than 1000 species. He argued that all Drosophila species "should be referred to by their scientific, not their common name."
Mel wrote that "real fruit flies, e.g., the Mediterranean fruit fly, the Oriental fruit fly, and other members of the family Tephritidae, attack unblemished fruit and in heavy infestations cause serious economic damage. In contrast, even if present in enormous numbers, D. melanogaster is innocuous and of no economic importance."
But to a "layperson's unsophisticated eye," the insects hovering over a fruit bowl, evoke the term, evoke "fruit fly," not "vinegar fly," the geneticist wrote.
The UC Davis campus bursts with buildings named for outstanding faculty, including:
- Asmundson Hall, named for Professor Vigfus Asmundson
- Briggs Hall,named for Professor Fred N. Briggs
- Everson Hall: Professor Gladys Everson
- Hutchison Hall: Professor Claude B. Hutchison
- Kleiber Hall: Professor Max Kleiber
- Bainer Hall: Professor Roy Bainer
And now, the list includes Green Hall, a fitting tribute to the careers of Melvin and Kathleen Green. (See UC Davis news story)
- Author: Kathy Keatley Garvey
And that's just a small portion of what they do.
And what a difference they're making!
Four UC Davis entomologists won awards from the Pacific Branch, Entomological Society of America (PBESA). They will be honored at the PBESA conference set for March 31-April 2 in San Diego.
Molecular geneticist/physiologist Joanna Chiu won the Physiology, Biochemistry, and Toxicology Award; pollination ecologist Neal Williams, the Plant-Insect Ecosystems Award; doctoral candidate Brendon Boudinot, the John Henry Comstock Graduate Student Award, the highest PBESA graduate student award; and UC Davis doctoral graduate Jessica Gillung, the Early Career Award.
Joanna Chiu is a newly selected Chancellor's Fellow, a five-year prestigious honor given to what Chancellor Gary May calls “prolific scholars, strong teachers, effective mentors and dedicated contributors to campus whose work is novel, unique and cutting-edge, groundbreaking and pathbreaking.”
Chiu investigates the regulation of animal circadian rhythms in her laboratory by using a combination of molecular genetics, biochemical, genomic, proteomic, and metabolomic approaches. Her overall research goal: to dissect the molecular and cellular mechanisms that control the circadian clock in animals, and to investigate how this endogenous timer interacts with the environment and cellular metabolism to drive rhythms of physiology and behavior.
Among the insects she studies: the spotted-wing drosophila, Drosophila suzukii.
"She has published a considerable amount on the spotted-wing drosophila, including its annotated genome, resistance studies, molecular basis of the so-called ‘winter morphs that are found in colder areas, and a molecular diagnostic for quickly providing species identification for all stages of this pest to distinguish it from other common Drosophila species," said emeritus Frank Zalom, UC Davis distinguished professor of entomology and a past president of the 7000-member Entomological Society of America.
"I can honestly say that in my 40 years on the faculty at UC Davis and earlier at the University of Minnesota, I have
never had the opportunity to work with a more collaborative and energetic early career scientist than Dr. Chiu," Zalom said.
Chiu, along with Professor Jay Rosenheim and associate professor Louie Yang of the UC Davis Department of Entomology and Nematology, are co-founders and co-directors of the highly successful, campuswide Research Scholars Program in Insect Biology. She helps students conduct cutting-edge research and provides guidance and advice, even after they have embarked on their own careers. Under her tutelage, many of her students are first authors of publications in prestigious journals.
Neal Williams "is widely known and respected for his excellence in research, extension, outreach, teaching, leadership and mentoring," said nominator Steve Nadler, chair of the Department of Entomology and Nematology. “He is a leading voice in the development of collaborative research on insect ecology. He has organized national and international conferences, leads scores of working groups, and guides reviews of impacts of land use and other global change drivers on insects and the services they provide.”
Williams focuses his research on the ecology and evolution of bees and other pollinator insects and their interactions with flowering plants. His work is particularly timely given concern over the global decline in bees and other pollinators.
Research entomologist James P. Strange of USDA's Bee Biology and Systematics Laboratory at Utah State University, describes Williams as “a valuable resource and prolific scientist in pollination biology and pollinator management. His papers are the result of collaborations with leaders in pollinator ecology, behavior and management and have been cited over 13,000 times during his career. His work has unraveled several questions central to plant-pollinator interactions, especially illuminating our understanding of the impacts of landscape resources on pollinator populations.”
In July, Williams will co-chair the Fourth International Conference on Pollinator Biology, Health and Policy at UC Davis. The four-day conference, themed “Multidimensional Solutions to Current and Future Threats to Pollinator Health,” will highlight recent research advances in the biology and health of pollinators, and link to policy implications.
Williams is also organizing a symposium at the PBESA's San Diego meeting in April on the lifelong contributions of native pollinator specialist, Robbin Thorp, UC Davis distinguished emeritus professor of entomology. Nine scientists influenced by Thorp and his research program will speak.
Brendon Boudinot, who studies with ant specialist/professor Phil Ward, was praised for his academic record, leadership, public service activities, participation in professional activities, and his publications. “A highly respected scientist, teacher and leader with a keen intellect, unbridled enthusiasm, and an incredible penchant for public service, Brendon maintains a 4.00 grade point average; has published 12 outstanding publications on insect systematics (some are landmarks or ground-breaking publications); and engages in exceptional academic, student and professional activities,” Nadler wrote.
Ward said that Boudinot, despite being at an early stage of his academic career, has already published several landmark papers on insect systematics. "This includes a remarkable article, just published in Arthropod Structure & Development, in which Brendon presents a comprehensive theory of genital homologies across all Hexapoda (Boudinot 2018). Based on careful comparative morphological study and conducted within a phylogenetic framework, this paper is a major contribution to the field and is destined to become a “classic." This could have been a decade-long study by any investigator, and yet it is just one chapter of Brendon's thesis!"
Active in PBESA and ESA, Boudinot received multiple “President's Prize” awards for his research presentations at national ESA meetings. He organized the ESA symposium, “Evolutionary and Phylogenetic Morphology,” at the 2018 meeting in Vancouver, B.C. , and delivered a presentation on “Male Ants: Past, Present and Prospects” at the 2016 International Congress of Entomology meeting in Orlando, Fla.
Boudinot served on—and anchored—three of the UC Davis Linnaean Games teams that won national or international ESA championships. The Linnaean Games are a lively question-and-answer, college bowl-style competition on entomological facts played between university-sponsored student teams.
Boudinot has served as president of the UC Davis Entomology Graduate Student Association since 2006, and is active in the campuswide UC Davis Picnic Day; he has co-chaired the department's Picnic Day Committee since 2017.
Jessica Gillung studied for her doctorate with major professor Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology. “Dr. Gillung has made outstanding contributions to entomology, shown commitment to extension or outreach, and excelled in entomological education,” Kimsey wrote in her letter of nomination. “In one word: she is ‘phenomenal.'"
Gillung most recently won the “Best Student Presentation Award” at the ninth annual International Congress of Dipterology, held in Windhoek, Namibia, and the 2018 PBESA Student Leadership Award. Her dissertation was titled: “Systematics and Phylogenomics of Spider Flies (Diptera, Acroceridae).”
Kimsey praised her phenomenal leadership activities, her nearly straight-A academic record (3.91 grade point average), her excellence as an entomologist and teacher, and her incredible publication record. “Note that she has 11 refereed publications on her thesis organisms in very strong journals,” Kimsey wrote. “Most entomologists do not publish nearly that much, even as a postdoctoral scholar or a junior faculty member!”
"Not only is Jessica's research on the cutting edge of the field of phylogenomics but--and this is where leadership comes in--she has taken it upon herself to involve and train other graduate students in the same cutting-edge techniques and theoretical framework," Kimsey said. "She is a dynamo--brilliant and high energy, but also constantly teaching."
A native of Brazil, Gillung speaks four languages fluently: Portuguese, Spanish, English and German. While at UC Davis, Gillung was active in PBESA and ESA, presenting a number of presentations and serving on award-winning Linnaean Games teams. In outreach programs, she reached at least 20,000 people encompassing all events from 2013 to 2018. This included open houses, off-site programs, science presentations, summer camps, classroom activities, UC Davis Picnic Days, agriculture days, and fairs and festivals.
As a postdoctoral researcher at Cornell University in the Bryan Danforth lab, Gillung is researching Apoidea (stinging wasps and bees) phylogenomics, evolution and diversification.
PBESA Award Recipients
The complete list of PBESA recipients:
- CW Woodworth: Elizabeth Grafton-Cardwell, UC Riverside.
- PBESA Award for Excellence in Teaching: Allan Felsot, Washington State University
- PBESA Award for Excellence in Extension: Surendra Dara, UC Cooperative Extension
- PBESA Award for Excellence in Integrated Pest Management: Silvia Rondon, Oregon State University
- PBESA Systematics, Evolution, and Biodiversity Award: Christiane Weirauch, UC Riverside
- PBESA Physiology, Biochemistry, and Toxicology Award: Joanna Chiu, UC Davis
- PBESA Medical, Urban, and Veterinary Entomology Award: Rebecca Maguire, Washington State University
- PBESA Plant-Insect Ecosystems Award: Neal Williams, UC Davis
- PBESA Distinction in Student Mentoring Award: Gerhard Gries, Simon Frazier University, British Columbia
- PBESA Excellence in Early Career Award: Jessica Gillung, UC Davis
- John Henry Comstock Graduate Student Award: Brendon Boudinot, UC Davis
- PBESA Student Leadership Award: Kelsey McCalla, UC Riverside
PBESA is one of six branches of the Entomological Society of America (ESA). Founded in 1889, ESA is the world's largest organization serving the professional and scientific needs of entomologists and individuals in related disciplines. It is comprised of more than 7000 members, who are affiliated with educational institutions, health agencies, private industry, and government. Members are researchers, teachers, extension service personnel, administrators, marketing representatives, research technicians, consultants, students, pest management professionals, and hobbyists.
- Author: Kathy Keatley Garvey
His seminar, part of the department's weekly seminars, is from 4:10 to 5 p.m., Wednesday, Feb. 13 in 122 Briggs Hall, off Kleiber Hall Drive. The title: "Understanding the Molecular Mechanisms Underlying Photoperiodic Time Measurement in Drosophila melanogaster."
"I will talk about the molecular mechanisms involved in seasonal adaptation in insects," Brieux said. "Overwintering insects undergo profound physiological changes characterized by an arrest in development and reproduction in adults, known as diapause. While the hormonal control of reproductive diapause is relatively well described it is still unclear how organisms interpret variations in photoperiod (daylength) and temperature to modulate their physiology in order to survive through unfavorable seasons."
"In this context I will present the progress we made in the characterization of a key mechanism signaling seasonal changes in insects and how it can promote our understanding of animal seasonal timing in a comparative framework. In addition, future work on this aspect is also expected to have a broad significance in understanding the evolutionary response of pest insects to rapid climate change."
Says Brieux: "Arguably, the most well recognized seasonal response in insects is the induction of overwintering diapause, which can be induced at different life stages, and is characterized by arrest in growth and reproduction. Since PPTM is critical to seasonal adaptation in insects, it has been studied extensively. Yet, the molecular and neuronal basis of the insect photoperiodic timer has evaded characterization."
The overall goal of this study, he says, is "to address the long-standing knowledge gap using the genetically tractable Drosophila melanogaster and the migratory butterfly, the monarch, Danaus plexippus, as complementary model."
"Specifically, we propose to investigate the mechanisms by which the seasonal timer interprets and signals changes in photoperiod to elicit downstream neuroendocrine and physiological responses in insects."
D. melanogaster "continues to be widely used for biological research in genetics, physiology, microbial pathogenesis, and life history evolution," according to Wikipedia. "As of 2017, eight Nobel prizes had been awarded for research using Drosophila."
Brieux received his bachelor's degree in biology in 2009 and pursued a master's degree from Pierre and Marie Curie University, Paris, France. He finished his doctorate in 2014 with faculty members Line Duportets and Christophe Gadenne at Angers University, western France, where he investigated the role of hormones and biogenic amines in the behavioral response to the sex pheromone in the noctuid Agrotis ipsilon.
The postdoctoral scientist joined the Chiu lab in the spring of 2016. In addition to his passion for research, Brieuz is a talented photographer passionate about macrophotography. Check out his photos on his website.
Associate professor Joanna Chiu, a molecular geneticist and physiologist, serves as the vice chair of the UC Davis Department of Entomology and Nematology, and is a newly selected Chancellor's Fellow. Her research expertise involves molecular genetics of animal behavior, circadian rhythm biology, and posttranslational regulation of proteins.
- Author: Kathy Keatley Garvey
Those are some of the questions that Wolf asks. "We aim to find some of the molecular and neural circuit mechanisms that govern adult behavior in the fruit fly Drosophila."
Wolf, who holds a doctorate in molecular and cell biology from UC Berkeley, will speak on "Drinking Drosophila and Drunk Drosophila: Genes and Circuits for Simple Behaviors" at the next UC Davis Department of Entomology and Nematology seminar, set for 4:10 p.m., Wednesday, Oct. 31 in 122 Briggs Hall.
"How is motivation coded in a small brain?" Wolf asks. "How does a natural motivation like a thirst differ from drug-seeking in addiction? We use circuit mapping, genetics and behavior in Drosophila melanogaster to find out internal states combine with environmental information to select behavioral programs and suppress others."
Molecular geneticist Joanna Chiu, associate professor and vice chair of the UC Davis Department of Entomology and Nematology, will introduce the speaker and serve as the host. Medical entomologist Geoffrey Attardo coordinates the fall seminars.
The Drosophila fly nervous system is remarkable. Wolf says it's "a million-fold simpler than ours, yet flies are capable of carrying out remarkably sophisticated tasks that are modified by past experience and internal states. However, the biological bases for even simple behavioral actions that serve as models for more complex tasks remain mysterious. Understanding how circuits function in a model organism where rapid progress can be made with highly sophisticated tools is likely to provide insight into how more complicated brains work."
No wonder that Drosophila melanogaster, is a favorite model organism among biomedical researchers.
"There are many technical advantages of using Drosophila over vertebrate models; they are easy and inexpensive to culture in laboratory conditions, have a much shorter life cycle, they produce large numbers of externally laid embryos and they can be genetically modified in numerous ways," according to Barbara Jennings in ScienceDirect.com. "Research using Drosophila has made key advances in our understanding of regenerative biology and will no doubt contribute to the future of regenerative medicine in many different ways."
"Over the past four decades," Jennings points out, "Drosophila has become a predominant model used to understand how genes direct the development of an embryo from a single cell to a mature multicellular organism." Indeed, numerous scientists have won Nobel Prizes for their research on the fruit fly.
What does the scientific name, Drosophila melanogaster, mean? Drosophila means "dew lover" and melanogaster means "dark gut."
- Author: Kathy Keatley Garvey
Researchers in the Walter Leal lab, UC Davis Department of Entomology, are engaging in some exciting research.
They just discovered a "generic insect repellent detector" in the fruit fly (Drosophila melanogaster)--research published today (March 16) in PloS One (Public Library of Science).
What's exciting is that this research may lead to more effective and lower-cost products than DEET, the gold standard of insect repellents.
The five-member team found the sensory organs involved when fruit flies detect and avoid three key insect repellents: DEET, IR3535 and picaridin. They identified the olfactory receptor neuron (ORN) and characterized its receptor, DmOr42a.
The research team of Leal; primary author and chemical ecologist Zain Syed; chemical ecologist Julien Pelletier; and undergraduate students Eric Flounders and Rodrigo Chitolina, first found that the fruit fly avoids all three well-known repellents, DEET, IR3535 (a compound known as Avon Corporation’s “Skin-So-Soft Bug Guard”) and picaridin (derived from pepper) and then set out to find olfactory receptor neurons sensitive to those insect repellents. They scanned all olfactory sensilla in the antennae and the mouthpart structure, maxillary palps, using single unit electrophysiological recordings.
The receptor they found “fulfills the requirements for a simplified bioassay for early screening of test insect repellents,” they wrote in the scientific paper.
When you think that it takes about 10 years and $30 million to develop a new repellent--and only one test compound in 20,000 reaches the market--this could really speed up the process.
Zain Syed told us: "In this study, by using established behavioral assays to dissect the mechanism of repulsion in fruit flies, we demonstrated for the first time that Drosophila equally avoid other repellents--picaridin and IR3535. By challenging every type of olfactory sensilla on the antenna and maxillary palps, we identified neurons and then the odorant receptor that detect these repellents."
The UC Davis research, as Syed said, "adds a new dimension in research towards understanding the molecular, cellular and organismal response to repellents."
Chemical ecologist Coby Schal, the Blanton J. Whitmire Distinguished Professor of Entomology at North Carolina State University, praised the research as “an excellent example of translational research that can lead to a streamlined and less expensive path of discovery of new repellents.”
In earlier research, Syed and Leal identified a DEET-sensitive olfactory receptor neuron in the Southern House mosquito. “Going from the neuron to the receptor, however, is like looking for the proverbial needle in a haystack as the mosquito genome has some 181 olfactory receptor genes,” Schal said.
The Leal lab knows DEET. Back in August 2008, Leal and Syed drew international attention when they announced they'd discovered DEET’s mode of action or how it works. Scientists long surmised that DEET masks the smell of the host, or jams or corrupts the insect’s senses, interfering with its ability to locate a host. The Leal-Syed research showed that mosquitoes actually smell DEET and avoid it because they dislike the smell.
DEET, developed by scientists at the U.S. Department of Agriculture and patented by the U.S. Army in 1946, is the go-to insect repellent. Worldwide, more than 200 million use DEET to ward off vectorborne diseases.
