- Author: Kathy Keatley Garvey
The research, “Circabidian Rhythm of Sex Pheromone Reception in a Scarab Beetle,” published in the Jan. 18 edition of Current Biology, marks the first sex pheromone receptor identified in Coleoptera, the order of beetles.
While most insects exhibit a 24-hour circadian rhythm that regulates their behavior and physiology, the large black chafer beetle, Holotrichia parallela, operates on a 48-hour clock, said Leal, a global expert on insect olfaction and communication. A professor in the Department of Molecular and Cellular Biology, he is a former professor and chair of the UC Davis Department of Entomology, now the Department of Entomology and Nematology.
“Insects smell with their antennae,” said Leal, who has unraveled the molecular mechanisms of mosquitoes, true bugs, long horned beetles, moths and other insects. “They have a sophisticated olfactory system and can selectively detect minute amounts of odorants.”
The female H. parallela emerges from the soil every other night, after sunset, climbs the canopy of the host plant, and seeks a mate by releasing a sex pheromone. Leal wanted to know if the males are also on a 48-hour rhythm clock, and he wanted to identify the elusive male gene in the pheromone receptor that allows the male to scent the female's pheromone.
The answers: “yes” and “yes.”
“I have been waiting for almost three decades to answer these questions,” Leal said. “I identified the sex pheromone of this beetle species in 1993 while working for the Ministry of Agriculture and Forestry of Japan. At that time, I found for the first time a very unusual sex pheromone, which is derived from an amino acid. Now similar sex pheromones have been identified from many species of beetles.”
“Also, we showed that females produce the sex pheromone every other night,” Leal said. “The burning question in biology is what males do about sensing or smelling the female sex pheromone. Back then, we had no idea how insects sense smell. With the advancements in sequencing, we identified all potential receptors and identified which one senses the sex pheromone. COVID happened and delayed our research collaboration. Finally, we found that the receptor is expressed every other day.”
“This is remarkable,” Leal said. “How do they know when it is a 'date night' or a non-calling night? It is still a mystery, but we will find out one day.”
Leal and Yin and their team pointed out that virtually all life on Earth experiences a 24-hour circadian rhythm, which affects almost all behaviors, including sexual activity and mating.
Leal, a native of Brazil, received his Ph.D. in applied biochemistry from the University of Tsukuba, Japan, with subsequent postdoctoral training in entomology and chemical ecology at the National Institute of Sericultural and Entomological Science and Cornell University, respectively. He was the first non-Japanese person to earn tenure at Japan's Ministry of Agriculture, Forestry, and Fisheries.
Leal, who joined the UC Davis faculty in 2000, is a newly elected trustee of the Royal Entomological Society, the first UC Davis scientist to be elected a trustee. He chaired the UC Davis Department of Entomology in 2006-2008 before accepting a position in 2008 as professor of biochemistry in the Department of Molecular and Cellular Biology. His many honors include Fellow of the Entomological Society of America (2009), American Association for the Advancement of Science (2005), and the National Academy of Inventors (2019).
Other co-authors of the Current Biology paper: Yinliang Wang, Huanhuan Dong, Yafei Qu, Jianhui Qin, Kebin Li, Yazhong Cao and Shuai Zhang, Chinese Academy of Agricultural Sciences, Beijing; Yuxin Zhou and Bingzhong Ren, Northeast Normal University, Changchun, China; and Chen Luo, Beijing Academy of Agriculture and Forestry Sciences.
The research drew financial support from the National Key R&D Foundation of China; National Natural Science Foundation, China; and the Natural Science Foundation of Beijing.
Resources:
- For This Beetle, ‘Date Night' Comes Every Other Day, Jan. 18, 2024, Andy Fell, UC Davis News and Media Relations
- Walter Leal Elected Trustee of Royal Entomological Society, Sept. 5, 2023
- Author: Kathy Keatley Garvey
Beginning Jan. 1, 2024, Shapiro will be collaborating with the Bohart Museum of Entomology, the "dropping off point," for the Pieris rapae entries. Bohart curator and collections manager Brennen Dyer will be accepting the entries.
Shapiro launched the contest in 1972 as part of his scientific research to determine the first flight of the year in the three-county area. His research involves long-term studies of butterfly life cycles and climate change.
The contest begins at 12:01 Jan. 1. The prize is either a beer or an equivalent.
Shapiro says P. rapae is emerging earlier and earlier as the regional climate has warmed. "Since 1972, the first flight of the cabbage white butterfly has varied from Jan. 1 to Feb. 22, averaging about Jan. 20."
Shapiro, who maintains a research website at http://butterfly.ucdavis.edu/, says the point of the contest "is to get the earliest possible flight date for statistical purposes. The rules require that the animal be captured and brought in alive to be verified. That way no one can falsely claim to have seen one or misidentify something else as a cabbage white."
The contest rules include:
- It must be an adult (no caterpillars or pupae) and be captured outdoors.
- It must be brought in alive to the Bohart Museum of Entomology, located in Room 1124, Academic Surge Building, 455 Crocker Lane, UC Davis campus, during work hours, from 8 a.m. to noon, and from 1 to 5 p.m., Monday through Friday. It must include full data (exact time, date and location of the capture) and the contact information of the collector (address, phone number and/or e-mail.) Brennen Dyer will certify that it is alive and refrigerate it. (If it's collected on a weekend or holiday, it can be kept in the refrigerator for a few days--do not freeze it, Shapiro says.)
- Shapiro is the sole judge.
Feb 8 was "the 11th latest first rapae day since 1972,” he said, detailing the 10 later finds: Feb. 26, 1972 (“which is probably too late, since I hadn't yet learned where to look for them first!”); Feb. 22, 1992 (“I fully believe that one”); Feb. 18, 1978 and 1986; Feb. 17, 1979; Feb. 16, 1975; Feb. 14, 1981; Feb. 13, 1983 and 1985; and Feb. 10, 1980. “Note that most of these are from the '80s,” he said. “There has indeed been a trend to earlier emergence, though this year is an outlier!”
Shapiro says P. rapae inhabits vacant lots, fields and gardens where its host plants, weedy mustards, grow. The male is white. The female is often slightly buffy; the "underside of the hindwing and apex of the forewing may be distinctly yellow and normally have a gray cast,” Shapiro said. “The black dots and apical spot on the upperside tend to be faint or even to disappear really early in the season.”
Shapiro, who monitors butterfly populations in the field for more than 200 days of the year, participates in his own contest. He has been defeated only four times and those were by UC Davis graduate students. Adam Porter won in 1983; Sherri Graves and Rick VanBuskirk each won in the late 1990s; and Jacob Montgomery in 2016. The first three were his own graduate students.
Shapiro nets many of the winners in mustard patches near railroad tracks in West Sacramento, Yolo County
Recent Beer-for-a-Butterfly Contest statistics:
- 2023: Art Shapiro recorded the first butterfly of the year at 11:22 a.m., Feb 8 in West Sacramento County, Yolo County. He did not collect the specimen and no one can forth with a winner.
- 2022: No official contest due to the COVID pandemic, but Shapiro recorded his first-of-the-year P. rapae at 1:25 p.m. on Jan. 19 in West Sacramento, Yolo County
- 2021: No official contest due to the COVID pandemic, but Shapiro collected his first-of-the-year at 1:55 p.m. Jan. 16 on the UC Davis campus, Yolo County
- 2020: Technically, no winner, as Shapiro did not collect the one he spotted in Winters, Yolo County at 11:16 a.m. on Jan. 30 at the Putah Creek Nature Park. "It flew back and forth across Putah Creek and then departed the area, flying out of reach above the trees," he noted. He waited around for 90 minutes to see if it would return. It did not.
- 2019: Shapiro collected the first cabbage white butterfly near the Suisun Yacht Club, Suisun City, Solano County, at 1:12 p.m., Friday, Jan. 25. "It was the earliest recorded in Suisun City in 47 seasons."
- 2018: Art Shapiro collected the winner in West Sacramento
- 2017: Jan. 19: Art Shapiro collected the winner on the UC Davis campus
- 2016: Jan. 16: Jacob Montgomery collected the winner in west Davis
- 2015: Jan. 26: Shapiro collected the winner in West Sacramento
- 2014: Jan. 14: Shapiro collected the winner in West Sacramento
- 2013: Jan. 21: Shapiro collected the winner in West Sacramento
- 2012: Jan. 8: Shapiro collected the winner in West Sacramento
- 2011: Jan. 31: Shapiro collected the winner in Suisun
- 2010: Jan. 27: Shapiro collected the winner in West Sacramento
A fellow of the American Association for the Advancement of Science, the Royal Entomological Society and the California Academy of Sciences, Shapiro is the author of A Field Guide to Butterflies of the San Francisco Bay and Sacramento Valley Regions, illustrated by Tim Manolis and published in 2007 by the University of California Press.
Collaborating with Shapiro on butterfly research projects is Foundation Professor Matthew Forister, the Trevor J. McMinn Endowed Research Professor in Biology, University of Nevada. Forister received his doctorate from UC Davis, studying with Shapiro, his major professor.
Pest of Cole Crops. As a caterpillar, the insect is a pest of cole crops such as cabbage. UC Statewide Integrated Pest Management Program (UC IPM) says the cabbageworm is active throughout the year in California. "Cabbageworm larvae chew large, irregular holes in leaves, bore into heads, and drop greenish brown fecal pellets that may contaminate the marketed product. Seedlings may be damaged, but most losses are due to damage to marketed parts of the plant," according to the UC IPM website.
The Bohart Museum of Entomology is directed by UC Davis distinguished professor Lynn Kimsey. Entomologist Jeff Smith curates the Lepidoptera collection, a global collection of some 500,000 moths and butterflies.
- Author: Kathy Keatley Garvey
It did: their research revealed how TSWV (family Tospoviridae, order Bunyavirales) packages its RNA genome, a crucial step in virus infection.
Their newly published research, “The Genome of a Bunyavirus Cannot be Defined at the Level of the Viral Particle But Only at the Scale of the Viral Population,” appears in the current edition of the Proceedings of the National Academy of Sciences (PNAS).
The 18-member research team included scientists primarily from the French National Research Institute for Agriculture, Food and Environment (INRAE) at the Campus International de Baillarguet, Montpellier; Department of Entomology, University of Wisconsin; and the Department of Entomology and Nematology, University of California, Davis.
“Our work showed the genome of TSWV can only be defined at the population level, pointing at emerging properties when viral particles infect plants in groups,” said a key author Stéphane Blanc, research director of INRAE's Biology and Genetics of Plant-Pathogen Interactions. “As most virions contain an incomplete genome, TSWV is a multi-component viral system, where co-infection and complementation are key in the life cycle. These findings open a myriad of possibly distinct properties depending on the genetic composition of the group of virions co-infecting a cell.”
“The most challenging part of this work was to create a protocol reliably quantifying the two polarities of each segment,” said lead author Michel Yvon of INRAE. “The next important advance will be to demonstrate that co-infection of cells by a group of particles is key to the spread of infection.”
Ullman, an international authority on orthotospoviruses and one of the four main authors, took a sabbatical to work on the project. “My interest was in understanding how TSWV packaged its RNA genome,” she said. “While this sounds like a simple goal, it is quite complex because TSWV has negative sense and ambisense viral strands and many research tools common to studying other viruses, such as infectious clones were not available.”
“It was a delight to work with the fantastic team of scientists that Stéphane assembled, all very talented with skills in virology, cryoelectron microscopy and nanopore PCR,” Ullman commented. “I cannot imagine a more talented and diverse group of people to conduct this difficult work. I learned a great deal about virus purification from Michel Yvon, whose leadership, skills in virology, and patient teaching really moved our project forward."
German, professor emeritus and former chair of both the Departments of Plant Pathology and Entomology at the University of Wisconsin, died Aug. 27, 2023 at age 82.
“I am indebted to my husband, Jean-Marc Leininger who frequently drove me to the laboratory in Avignon where I was able to rear thousands of virus-infected plants and to store TSWV isolate,” Ullman added. “Jean-Marc not only transported me and my virus specimens, but also learned to mechanically inoculate plants and helped with every inoculation and virus harvest.”
UC Davis postdoctoral scholar Sulley Ben-Mahmoud of the Ullman lab was among the co-authors.
Funding was provided by grants from Montpellier University of Excellence (MUSE); Floriculture and Nursery Research Initiative, U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS); and the Fulbright Scholar Program. The authors also acknowledged support from
- Santé des Plantes et Environnementor Plant Health and Environment (SPE)
- Centre National de la Recherche Scientifique (CNRS)
- Institute of Research for Development (IRD)
- Institut national de la santé et de la recherche médicale (INSERM)
- Centre for International Cooperation in Agronomic Research for Development (CIRAD)
- Plant Health Institute of Montpelier (PHIM)
Ullman noted the importance of the research in her Fulbright application: “Sustainable management of insect-transmitted pathogens is a key concern for food production in France and the United States. Both countries grow many of the same crops and growers face similar challenges from insect-transmitted plant viruses. Current management strategies rely heavily on pesticides that may cause significant health and environmental concerns, including damage to bees and other pollinators, as shown with neonicotinoid pesticides. Clearly, better knowledge about these insect-transmitted viral systems…has potential to reduce pesticide use by providing novel and innovative technologies to manage orthotospoviruses and thrips in France and the United States.”
Ullman, a former chair of the Department of Entomology and a former associate dean of the UC Davis College of Agricultural and Environmental Sciences, anticipates strong research relationships between UC Davis and Montpellier that will lead to grant applications for international research and scholarly exchange opportunities for scientists, students, and post-doctoral scholars.
Significance
In their significance statement, the authors wrote: “Bunyaviruses infect animals, plants, fungi, and protists. Despite their importance, fundamental aspects of their biology as basic as the definition of their genome remain elusive. The viral genome consists of several negative or ambisense RNA segments, and virions often miss segments and/or package complementary strands. We formally quantify this heterogeneity on the species Tomato spotted wilt orthotospovirus. Within individual virus particles, the number, the identity, and the polarity of the segments are widely variable. In contrast, we show that a stable genetic composition is an emerging property of the viral population, each of the RNA segments/polarities accumulating reproducibly at a specific frequency. This resembles the genome formula of multipartite viruses, suggesting that bunyaviruses may also function as multicomponent viral systems.”
Their abstract: “Bunyaviruses are enveloped negative or ambisense single-stranded RNA viruses with a genome divided into several segments. The canonical view depicts each viral particle packaging one copy of each genomic segment in one polarity named the viral strand. Several opposing observations revealed nonequal ratios of the segments, uneven number of segments per virion, and even packaging of viral complementary strands. Unfortunately, these observations result from studies often addressing other questions, on distinct viral species, and not using accurate quantitative methods. Hence, what RNA segments and strands are packaged as the genome of any bunyavirus remains largely ambiguous. We addressed this issue by first investigating the virion size distribution and RNA content in populations of the tomato spotted wilt virus (TSWV) using microscopy and tomography. These revealed heterogeneity in viral particle volume and amount of RNA content, with a surprising lack of correlation between the two. Then, the ratios of all genomic segments and strands were established using RNA sequencing and qRT-PCR. Within virions, both plus and minus strands (but no mRNA) are packaged for each of the three L, M, and S segments, in reproducible nonequimolar proportions determined by those in total cell extracts. These results show that virions differ in their genomic content but together build up a highly reproducible genetic composition of the viral population. This resembles the genome formula described for multipartite viruses, with which some species of the order Bunyavirales may share some aspects of the way of life, particularly emerging properties at a supravirion scale.”
- Author: Kathy Keatley Garvey
The 10 x 6-foot mural, which graces an outer wall of the Matthiasson Winery on Dry Creek Road, Napa, depicts more than 80 arthropods (insects, spiders and centipedes), several bird species, mammals (bobcat, deer, rabbits, squirrels, a pocket gopher), a gopher snake, mycorrhizal fungi and even earthworms, according to the three project leaders, UC Davis distinguished professor Diane Ullman and assistant professor Emily Meineke, both of the Department of Entomology and Nematology, and retired lecturer Gale Okumura of the Department of Design.
The project is the culmination of a spring quarter class, Entomology 001, “Art, Science and the World of Insects,” taught by Professors Ullman and Meineke. Ullman, founding co-director of the UC Davis Art/Science Fusion Program, described the project as “a collaboration between students and instructors in ENT 001; community members from Davis, Woodland, and Napa, and Matthiasson Winery; and the UC Davis Art/Science Fusion Program."
Praising the Arts/Science Fusion Program, the chancellor said the program "helps advance some of UC Davis' key goals, which are outlined in the university's 10-year strategic plan, titled 'To Boldly Go.' That first goal is to provide an educational experience that prepares all our students to address the needs and challenges of a diverse and changing world. The type of course that produced this mural helps advance this goal, by connecting art and science to enhance student learning in a truly innovative way. Another key goal is for UC Davis to be a role model for diversity. This program's strategy for teaching always includes community engagement, which attracts diverse students and fosters inclusivity through hands-on learning and collaborative teamwork. I also appreciate how the Arts/Science Fusion Program fosters community engagement."
Ullman noted that the general education class, "Art, Science and the World of Insects," was founded in 1996. It's been taught ever year since, "attracting students from every major offered on the UC Davis campus," she said.
The course--"taught with the notion that patterns, harmonies, symbols, and perceptions are shared across borders and disciplines--creates accessibility and inclusion for people that would otherwise fear science, or fear art," Ullman told the crowd. "Not only does this paradigm provide a new and innovative classroom learning experience, it creates collaborations between different kinds of students and the community."
The concept of an art/science paradigm "opened the door for students and community members to interpret the scientific endeavors of the campus and science of entomology," said Ullman, praising the College of Agricultural and Environmental Sciences "that supports this innovative method of teaching and extending knowledge to the public."
After advancing from research to a primary design, "the next step was to translate our research into visual narratives using design principles we learned from Gale," Ullman said. "With our designs in hand, the process of fabricating the artwork from clay began. Clay is a rich material with great memory, coming from the earth near Davis. In our classroom, every piece is used, recycled and carried forward."
"Once all the pieces of have been sculpted, glazed and fired in a kiln, assembly of the mosaic begins," Ullman related. "Everyone, students and community members contributed to assembly and grouting of the mosaic—truly a mosaic of human intention, creativity and will. We mixed our own grout and each color is custom designed after experimentation and consideration. Most artists would ask for 6 months to a year to complete a project of this size and scope. We completed the process in a mere 10 weeks, the scope of a quarter at UC Davis."
Ullman said that the 83 UC Davis students involved in the project "worked hard, learned about entomology, and the interactions between insects and people."
Meineke, an urban landscape entomologist, was unable to attend the Aug. 16th unveiling. Meineke and her husband Joe Kwon just "brought our newest Aggie, Genevieve Se Hwa Kwon into the world," Ullman told the gathering.
In a joint statement, Ullman and Meineke related that The Secret Life of Vineyards was designed to reflect the ecosystem within and around an organic vineyards as it progresses from early spring to harvest. A Cabernet Sauvignon vine is the centerpiece of the mural, shown from the first bud in the spring to harvest time in the autumn...The work is an ode to the importance of biodiversity and balance in the ecosystem in which wine vines are grown and reflects the passion of the Matthiasson Winery for sustainable viticulture.”
The professors credited artist Amanda Larson of Half Moon Bay "with the engineering and building of the hanging system, as well as the installation."
Resources:
- UC Davis Mural to Be Unveiled, news story, published Aug. 8, 2023, on the UC Davis Department of Entomology and Nematology website
- PowerPoint detailing the project from start to finish. This includes artist statements.
- Author: Kathy Keatley Garvey
A familiar figure at UC Davis, he served as an associate of the Bohart Museum of Entomology and a scientific collaborator, identifying scores of insects and attending many of the Lepidopterist Society meetings there.
Plans call for dedicating the Bohart Museum's "Night at the Museum" (formerly known as "Moth Night") to him. The open house, free and open to the public, is set from 7 to 11 p.m., Saturday, July 22. The museum is located in Room 1124 of the Academic Surge Building, 455 Crocker Lane, UC Davis, campus.
Born May 23, 1933 in Glendale, Calif., Jerry received his bachelor's degree in entomology at UC Berkeley in 1955 and his doctorate there in 1961. One of his most-read books, co-authored with Charles Hogue, is California Insects, Volume 44, published in 1980. The second edition, co-authored by Kip Will, Daniel Rubinoff and Powell was published in October, 2020. Powell and Paul Opler 1938-2023) co-authored Moths of Western America, published in 2009.
In a tribute to Powell on its website, the Essig Museum posted in part:
"In his teen years he was heavily influenced by Charles 'Harbie' Harbison, who ran the Junior Naturalist Program at the San Diego Museum of Natural History, and sparked an interest in Jerry for butterflies and moths. Seeing his potential, Harbie recommended Jerry for the Entomology program at UC Berkeley, where he received his BS in 1955 and his PhD in 1961. While climbing through the ranks of Junior Entomologist (1961-62), Assistant Entomologist (1962-67), Associate Entomologist (1967-73), Entomologist (1973-94), Lecturer in Entomology (1964-69), Associate Professor (1969-73), and Professor (1973-94) at UC Berkeley, Jerry also became Curator (1972-2018) and Director (1993-1999) of the Essig Museum of Entomology (1972-1999) and Project Leader for the California Insect Survey (1963-1999). Although he retired as Director in 1999, Jerry remained a professor of the Graduate School until 2012 and maintained an active research program in Lepidoptera life histories and systematics until 2018, advising many students along the way. (See more on Essig website.)
"Jerry's rearing program was the most extensive in the history of the study of New World Microlepidoptera," according to the Essig post. "For over 50 years he and his students processed more than 15,000 collections of larval or live adult Lepidoptera. Resulting data encompass more than 1,000 species of moths, through rearing either field-collected larvae or those emerging from eggs deposited by females in confinement. This total includes more than 60% of an estimated 1,500 species of Microlepidoptera occurring in California."
Powell gained international recognition when he detected the agricultural pest, the light brown apple moth, Epiphyas postvittana, in a ultralight (UV) trap on July 19, 2006 in his backyard in Berkeley.
"Yet Powell's casual discovery that morning was just the beginning of something more serious: a moth infestation, a quarantine program and an all-out effort by state and federal authorities to stop a nasty creature that they concluded could threaten California's $38 billion agricultural market and--if unchecked--farms across the nation," wrote San Francisco Chronicle reporter Matthew B. Stannard in a June 3, 2007 piece, "Little Moth, Big Problem/Bay Area quarantine tries to halt the spread of ravenous pest."
In an email to colleagues on July 9, Peter Oboyski, executive director of the Essig Museum of Entomology, wrote in part: "With a heavy heart I am sad to report that professor Jerry Powell passed away this weekend. His contributions to our knowledge of California entomology, microlepidoptera, and insect life histories are inestimable, as is the value of the training he provided to his students. As one of those students, I am eternally grateful for the time, energy, and knowledge Jerry shared with me in the museum and the field."
"A consummate field biologist, Jerry's knowledge and interests were broad, allowing him to read landscapes and discover the most interesting and cryptic of species interactions," Oboyski wrote. "This is well documented in over 220 publications, but also in the 60+ years of his field notes and rearing records that we are currently digitizing. He is the collector of over 400 holotypes of various insect orders, described over 170 species and 14 genera of moths, and honored by 41 patronyms. He also published papers on Hymenoptera, Coleoptera, Diptera, Dermaptera, and a Nematode. His legacy is impressive and will long be remembered."
Powell described himself as a "MothNut" on his vehicle license plate, and also displayed a sticker, "Larvae on Board."