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.
More than 2000 scientists are registered to attend the meeting, to be held Sept. 2-6 in Gramado, Brazil.
UC Davis scientists delivering plenary addresses will be Frank Zalom, distinguished professor of entomology, UC Davis Department of Entomology and Nematology and a past president of the Entomological Society of America (ESA); Walter Leal, distinguished professor, UC Davis Department of Molecular and Cellular Biology, and a past chair of the Department of Entomology and Nematology; and Joanna Chiu, associate professor and vice chair, UC Davis Department of Entomology and Nematology. More than 2000 attendees are registered.
On behalf of ESA, Zalom is co-organizing and co-chairing a joint conference with Antonio Panizzi, a past president and international delegate of the Entomological Society of Brazil. That event, to take place the day before the XXVII Congresso Brasileiro and X Congresso Latino-Americano meeting, will involve developing a “Grand Challenge Agenda for Entomology in South America.
Zalom will speak on “The American Experience with the Grand Challenge Agenda in Entomology.” In addition, ESA president Michael Parrella, dean of the College of Agricultural and Life Sciences at the University of Idaho and a former chair of the UC Davis Department of Entomology and Nematology, will provide an update on the 2018 ESA annual meeting, set Nov. 11-14 in Vancouver, B. C. Speakers also will include the presidents of the entomological societies of Argentina, Peru and Brazil.
Leal, a native of Brazil, will present the opening lecture of the joint conference of the XXVII Brazilian Congress and X Latin American Congress of Entomology on “Insect Vectors: Science with Applications in Agriculture and Medicine,” on Sunday, Sept. 2. This will be his fourth opening lecture—a record—at the Brazilian Congresses of Entomology (2004 in Gramado; 2008 in Uberlandia; and 2014 in Goiania). As an aside, legendary entomologist Marcos Kogan previously held the record: he presented two opening lectures, one in 1983 and another in 2002. Both Leal and Kogan (professor emeritus of agricultural entomology, University of Illinois and professor emeritus, Oregon State University) were elected ESA fellows; Leal in 2009 and Kogan in 2016. Zalom received the honor in 2008.
Zalom, an integrated pest management specialist, and former director of the UC Statewide Integrated Pest Management Program (UC IPM) and Chiu, who specializes in molecular genetics of animal behavior, will speak on their research at the joint meeting. Zalom will deliver a plenary address on “Drosophila suzukii in the United States” on Sept. 5, and Chiu will keynote a symposium on Sept. 3; her lecture is titled “Circadian Clock Research Applied to Agriculture and Public Health.” She will give a second lecture: "Drosophila as an Insect Model" on Sept. 3.
The spotted wing drosophila (SWD) is a serious pest of fruit crops. Most drosophila flies feed on spoiled fruits, but SWD prefers fresh fruit (berries and soft-skinned fruits). Read more about SWD on the UC IPM website.
So begins National Public Radio science journalist Richard Harris in his chapter, “Broken Culture," in his newly published book, Rigor Mortis: How Sloppy Science Creates Worthless Cures, Crushes Hope and Wastes Billions.
Darwin was driven by curiosity; he didn't start out with a “coherent hypothesis,” Harris says. Plus, Darwin "had no need to hustle for money,” and "he was in no hurry to publish his discoveries.”
Today the “high pressure of competition can tempt even the best scientists into dangerous territory,” Harris warns in his 278-page book.
You can hear what Harris says about sloppy science/faulty research when he travels from his home in Washington, D.C. to the University of California, Davis, campus to deliver a Storer Lecture.
Harris will speak on “Common Errors that Bedevil Biomedical Research and How to Fix Them,” from 4:10 to 5 p.m., on Wednesday, Oct. 25 in the UC Davis Student Community Center. The event is free and open to the public. A book signing will follow the lecture.
The lectureship, established in 1960, is funded through a gift from Professor Tracy I. Storer and Dr. Ruth Risdon Storer to bring eminent biologists to the UC Davis campus. Speakers have included Nobel laureates, members of the National Academy of Science and acclaimed authors in the life sciences and medicine.
“Richard Harris has written a very important and unsettling book based on his careful investigation of the biomedical research enterprise,” said Mark Winey, distinguished professor of Molecular and Cellular Biology and dean of the College of Biological Sciences, UC Davis, who is hosting the journalist. “We can expect an intriguing and thought provoking lecture.”
In his book, Harris relates that American taxpayers spend $30 billion annually funding biomedical research. “We all rely on biomedical research for new treatments and cures,” Harris points out. “But this critical enterprise is not in the best of health itself. Most experimental treatments fail. One reason is that the underlying research does not hold up to scrutiny. Scientists find that far too often that they are unable to repeat experiments that other researchers have carried out.”
By some estimates, half of the results from these studies can't be replicated elsewhere—the science is simply wrong, Harris asserts.
The national award-winning science journalist, who grew up in the San Francisco Bay Area, has covered science, medicine and the environment for NPR Radio since 1986. A graduate of UC Santa Cruz with a bachelor's degree in biology, he began his journalism career as a reporter for the Livermore (Calif.) Tri-Valley Herald. He later joined the San Francisco Examiner as a science writer. He is a past president of the National Association of Science Writers and the Northern California Science Writers' Association.
We just finished reading Rigor Mortis today. It's not only an eye opener, but a call to action. It's as easy to read as a well-documented and detailed newspaper investigative piece, complete with patient and researcher interviews and anecdotes. It zeroes in on “the constant scramble for research dollars” and the fact that scientists' “promotions and tenure depend on their making splashy discoveries.” Sadly, it's often quantity over quality in the "publish-or-perish" world of academia.
Harris writes about egregious research, targeting cancer, heart disease, Lou Gehrig's disease, diabetes, and other diseases--diseases that can and do affect us all, either through taxpayer funding or personal/family/friend experiences.
Charles Darwin was in no hurry to publish his discoveries. Neither should today's researchers. We can and must do better.
(Editor's Note: The presentation will be recorded for later viewing. Joanna Chiu, associate professor and vice chair, UC Davis Department of Entomology and Nematology, is coordinating the Storer Lectureships in Life Sciences for the academic year. She may be reached at firstname.lastname@example.org)
What a delight to see.
We strolled through milkweed patches in the UC Davis Arboretum Thursday noon and saw them.
The monarch butterflies (Danaus plexippus) are returning from their coastal California overwintering sites. And we're getting new generations.
The UC Davis campus, including the 100-acre UC Davis Arboretum is home to much celebrated flora and fauna, including milkweed and monarchs.
After overwintering along the California coast and in central Mexico, the butterflies flutter north into the United States and Canada in the spring and summer.
However, scientists report that the monarch population in central Mexico declined from 100 million last year to 78 million this year, due to late winter storms, coupled with cold and wet weather, and deforestration.
It's a sure sign of spring, through, when the monarchs return. It's a cause for celebration. Welcome back!
Meanwhile, we're anticipating the arrival of Christine Merlin, assistant professor in Texas A&M's Department of Biology, who will discuss her research on "The Monarch Butterfly Circadian Clock: from Clockwork Mechanisms to Control of Seasonal Migration" when she presents a seminar on Wednesday afternoon, May 31 at the University of California, Davis. The seminar is set from 4:10 p.m. to 5 p.m. in Room 122 of Briggs Hall. Host is molecular geneticist Joanna Chiu, associate professor and vice chair of the UC Davis Department of Entomology and Nematology.
Yes, they do, says a Texas A&M researcher.
Christine Merlin, an assistant professor in Texas A&M's Department of Biology, will discuss her research on "The Monarch Butterfly Circadian Clock: from Clockwork Mechanisms to Control of Seasonal Migration" when she presents a seminar on Wednesday afternoon, May 31 at the University of California, Davis.
The seminar is set from 4:10 p.m. to 5 p.m. in Room 122 of Briggs Hall.
"The eastern North American monarch butterfly (Danaus plexippus) has emerged as a powerful model system to study animal circadian clocks and their role in an unconventional output, the photoperiod-induced long-distance migration," Merlin writes in her abstract. "Circadian clocks are endogenous 24-hour timekeepers that coordinate nearly all of the animal physiology and behavior to its environment to tune specific activities at the most advantageous time of the day. Monarchs use a circadian clock to navigate to their overwintering sites during their seasonal long-distance migration."
"The clock time-compensates for the movement of the sun across the sky over the course of the day and regulates the sun compass output in the brain. Circadian clocks could also be used to time the monarch seasonal departure from their breeding grounds, and consequently regulate the genetic/epigenetic program controlling migratory physiology and behavior. I will discuss progress that our lab has made in developing reverse-genetics in the monarch butterfly to unlock its potential as a genetic model system to study animal clockwork mechanisms and the involvement of the circadian clock in insect photoperiodic responses."
Merlin will be hosted by molecular geneticist Joanna Chiu, associate professor and vice chair, UC Davis Department of Entomology and Nematology, who is also involved in circadian-clock research. The weekly seminars, chaired by assistant professor Christian Nansen, are open to all interested persons. Plans call for recording the seminar for later posting on UCTV.
A native of France, Merlin received her bachelor's, master's and doctoral degrees majoring in animal biology, invertebrate physiology and insect physiology, respectively, at the University Paris 6 Pierre and Marie Curie in France. She accepted a postdoctoral fellowship at the University of Massachusetts in 2007.
From her post at Texas A&M University, located at College Station, 90 miles northwest of Houston, Merlin enjoys a front-row seat for the monarch butterfly migration.
She sees them heading to Mexico to overwinter, and she sees them returning.
But it's the science that drives her.
In a Texas A&M news story, Vimal Patel described her as trying to unravel "the mysteries of the migration and the role of internal clocks in the process."
"It's incredible how such a fragile insect can complete a long-range migration so demanding," Merlin told Patel. "Every piece of it fascinates me, from how it occurs to why they go precisely where they go."
An excerpt from Patel's piece:
"While she was a postdoctoral researcher at the University of Massachusetts Medical School in the laboratory of Prof. Steven Reppert, Merlin and colleagues showed that the clocks necessary for flight orientation lie in the creatures' antennae --a departure from the previous conventional wisdom that the brain controlled the mechanism, given that it controls behavioral rhythmicity in virtually every other animal, including humans.
"The conclusion stemmed from Merlin's and her co-workers' collective curiosity concerning a decades-old anecdote. Around 50 years ago, entomologist Fred Urquhart found that Monarchs became disoriented after he clipped off their antennae. Since then, it had remained just a suspicion until the Massachusetts team confirmed it with more rigorous research."
"The team's experiment exploited technology in a way Urquhart, who merely observed the Monarchs in flight, could not at the time. They used a plastic barrel-like device called a Mouritsen-Frost flight simulator in which a butterfly is connected by tungsten wire to an output system that indicates which direction it is flying. The results were clear: The antennae-less Monarchs flew in every which direction, while those with intact antennae flew southwesterly, the migratory direction."
Merlin points out that "Migration begins every year in the fall, when the day lengths change. The shortened day lengths might be a cue for the monarchs to start their migration. And if we can show this is the case and that the circadian clock is involved, we can now start to understand the genetic program that is allowing the migratory behavior."