Mud crabs are a favorite snack for blue crabs. But when blue crabs pee in the water while searching for food, it sends their prey a warning: Better hide or urine trouble. (Sorry, we couldn't resist.) Researchers have known that chemicals in crab urine scare mud crabs, but couldn't identify the offending chemicals — until now, thanks to a new Georgia Tech study co-led by Julia Kubanek, a professor in both the School of Biological Sciences and the School of Chemistry and Biochemistry, and Marc Weissburg, a professor in the School of Biological Sciences. The findings could lead to better management of crab and oyster fisheries, and may even help target pollutants that upset marine life. Kubanek is also Associate Dean for Research for the College of Sciences.
Georgia Public Broadcasting radio host Celeste Headlee replays her 2015 interview with Patricia Yang, a doctoral student and co-winner of an Ig Nobel Award, an honor presented by Improbable Research given to science projects that "make you laugh, then make you think." Yang's award was for a study on animal urination, which involved monitoring and recording the bladder-emptying habits of 32 different mammals at Zoo Atlanta. Yang worked on the study with David Hu, an associate professor in the George W. Woodruff School of Mechanical Engineering and the School of Biological Sciences, with an adjunct appointment in the School of Physics.
Mark E. Hay, Regents Professor and Harry and Linda Teasley Chair in the School of Biological Sciences at Georgia Tech, is the recipient of the 2018 Gilbert Morgan Smith Medal of the National Academy of Sciences. The award recognizes excellence in published research on marine and freshwater algae.
The 2018 Smith Medal recognizes Hay’s research into algal science, which has influenced a generation of scientists and revealed numerous insights into the declining health of ocean ecosystems. His research has enormous implications for coral reef recovery, along with the ecosystems and human societies that depend upon these reefs.
Hay developed algal chemical ecology as the major model for marine chemical ecology, a field that he cofounded. He elucidated how chemical cues and signals from algae structure marine and aquatic populations, communities, and ecosystems.
An experimental ecologist, Hay led scientific expeditions to remote regions to study the processes and mechanisms that control the organization, function, and sustainability of natural ecosystems. His studies of seaweed – which comprise red, brown, and green marine algae – have revolutionized the practice of marine conservation and management.
“By conducting phycological studies within the broader intellectual framework of ecology and evolution, Mark extended the impact of his algal studies,” says James H. Tumlinson, the Ralph O. Mumma Professor of Entomology and Director of the Center for Chemical Ecology at Pennsylvania State University. “His research has informed the conservation of coral reefs and helped predict how coastal ecosystems will be altered by global change.”
Hay’s 40-year academic career features many discoveries about the natural history of seaweeds. Initially, he focused on the effects of physical factors and biotic interactions on algal ecology, Tumlinson says. Then Hay turned to seaweed-herbivore interactions, seaweed chemical defenses, and the roles they played in deterring herbivores, overcoming competitors, and organizing seaweed communities.
Insights from his research enabled Hay to predict that particular combinations of herbivores would be needed to stop seaweed damage to corals and the algal domination of reefs. “By manipulating herbivore diversity alone, Hay’s lab was able to prevent coral mortality and increase coral growth, thus demonstrating the applied potential of his research,” Tumlinson says. “More recent work demonstrates the critical role of algal chemical cues in fish and coral recruitment on Pacific reefs and the impact of these chemical cues on reef resilience.”
“His research has informed the conservation of coral reefs and helped predict how coastal ecosystems will be altered by global change.”
The Smith Medal is the latest of significant honors bestowed upon Hay. In 2016, Hay reaped three awards: He received the International Society of Chemical Ecology (ICSE) Silver Medal, the society’s highest honor. He was named Fellow of the Ecological Society of America. And Georgia Tech named Hay the recipient of the 2016 Outstanding Faculty Research Author Award, for producing the most impactful publications from Georgia Tech in the previous five years.
“We bask in the glow of Mark’s accomplishment,” says College of Sciences Dean and Sutherland Chair Paul M. Goldbart. “Through his research and education efforts, Mark serves as a role model inspiring countless students and colleagues. In his communication efforts, Mark sets a superb example that so many more of us need to emulate.”
Indeed, Hay’s outstanding scholarship is matched by his zeal in communicating his research and its ecological implications in ways that are understandable to the public. He has written articles for the New York Time’s Scientists At Work blog and given numerous interviews to broadcast media, including NPR, BBC, CBS, ABC, Voice of America, and Voice of Russia.
“Because the ecosystem I study is disappearing,” Hay says, “I’ve perceived the need to focus on senior decision makers that can make a difference in the very near term.” Lately, he has been speaking about environmental challenges at corporations like The Coca-Cola Company and at community organizations, such as Rotary Clubs. He continues to educate the world about the plight of endangered ecosystems by organizing international symposia and web-based global discussions.
Presented every three years, the Smith Medal consists of a gold-plated bronze medal and a $50,000 prize. The bequest of Helen P. Smith in memory of her husband, Gilbert Morgan Smith, established the award in March 1968. Gilbert Smith was a renowned botanist, a member of the National Academy of Sciences, and the first president of the Phycological Society of America.
When a filmmaker set out across the South Pacific Islands to collect stories of locals fighting climate change, he probably didn't expect to find a Georgia Tech student in Fiji. Cody Clements is a Ph.D. student in the School of Biological Sciences, in the lab of Mark Hay. But in Fiji, he's a coral gardener, tending to the ocean's coral reefs like they're his backyard garden. The stituation is dire. He has personally witnessed multiple mass bleaching events in Fiji. But he works to rehabilitate the reefs by replanting various species in coral communities. His work is documented in the video series Across the Salty Roads.
Amyloids are abnormal proteins that aggregate into fibrils, causing dreadful human diseases. They are strongly implicated in Alzheimer’s disease, a leading cause of dementia in elderly people. Mad cow disease, a neurodegenerative disease, results from infection by prions, which are amyloids that can spread between cells and organisms.
Despite voluminous research on amyloids and prions, researchers still cannot explain how harmless, normal protein sequences go awry and assume the deadly amyloid shape.
“The initial amyloid ‘nucleation’ is extremely difficult to investigate in animal models,” says Yury Chernoff, a professor in the School of Biological Sciences. “To begin with, initial nucleation is extremely rare. We have no idea where the initial amyloid ‘nucleus’ comes from and what promotes its formation. And then accumulation of an amyloid to detectable levels takes a very long time.”
For these reasons, Chernoff’s Georgia Tech team and collaborators in Germany and Russia (St. Petersburg State University, where Chernoff also directs a research group) turned to yeast as a model to study the human amyloids. They published their findings in the Journal of Biological Chemistry in early January 2018.
According to Chernoff, yeast also form prions, and the initial nucleation of a yeast prion is also rare. “However,” he says, “it is easier to detect prion nucleation in yeast that in humans, because it is possible to analyze large numbers of yeast cells, and because yeast prions cause easily detectable traits.”
The researchers fused mammalian amyloid-forming proteins to the yeast prion-forming protein. They found that the resulting chimeric proteins nucleate an amyloid state in yeast much more frequently than yeast prion-forming protein does on its own. “Because the resulting amyloid nucleus further converts a normal yeast protein,” Chernoff says, “amyloid formation could be detected by the appearance of an easily observable trait, such as growth on specific medium.”
The researchers successfully applied the method to several proteins, including amyloid beta (associated with human Alzheimer’s disease), PrP (associated with mad cow disease), alpha synuclein (associated with Parkinson’s disease), and amylin (associated with type II diabetes).
“This assay opens a wide window to the early stages of dreadful human diseases caused by abnormal protein aggregation,” Chernoff says. “The more we understand how these diseases originate, the better we can develop treatments.”
Beyond revealing how human proteins undergo amyloid nucleation, Chernoff says, the assay will help researchers discover factors affecting amyloid nucleation in cells, find agents that favor the development of diseases, and identify treatments and conditions that can prevent the triggering cause of a disease.
Chernoff’s Georgia Tech team working on this project included current Ph.D. student Pavithra Chandramowlishwaran and former Ph.D. student Meng Sun, who are co-first authors on the paper, as well as undergraduate researcher Kristin Casey and research scientist Andrey Romanyuk.
Growth of the specially designed yeast strain on a specific medium enables researchers to detect nucleation of disease-related fibrils by human amyloid beta protein, associated with Alzheimer’s disease.
This work was supported by grants from the National Institute of Aging, NIH (through Emory University’s Alzheimer’s Disease Research Center) and the Creutzfeldt-Jakob Disease Foundation, as well as the Russian Science Foundation and the Russian Foundation for Basic Research (to the St. Petersburg group).
Dan Taylor, the Yellow Jackets' strength and conditioning coach for men basketball, takes advantage of the biomechanics lab on campus in order to collect data on and improve the performance of his players. Young-Hui Chang, the founder of the lab and a professor in the School of Biological Sciences, doesn't mind. Chang can use the data for his reserach into intuitive physics: the idea that people (and animals) have an innate ability to predict the physical actions of the world around them.
Dan Taylor, the Yellow Jackets' strength and conditioning coach for men basketball, takes advantage of the biomechanics lab on campus in order to collect data on and improve the performance of his players. Young-Hui Chang, the founder of the lab and a professor in the School of Biological Sciences, doesn't mind. Chang can use the data for his reserach into intuitive physics- the idea that people (and animals) have an innate ability to predict the physical actions of the world around them.
Named after the Amazons of Greek myth, the Molly is a small freshwater fish that is challenging the established belief that asexual vertebrates are not viable long term. Each daughter is essentially a clone of her mother. Yet the Molly is thriving, perhaps for 10,000 years. Pedram Samani, an evolutionary geneticist and postdoctoral researcher in the School of Biological Sciences, comments on the research in Nature Ecology & Evolution. His comments are echoed by Cosmos Magazine.
Jenny McGuire is one of several scientists featured in a documentary that WyomingPBS will air twice in February. The documentary is part of a series called “Main Street, Wyoming.” The episode, “Natural Trap Cave,” is about a pitfall cave in the Bighorn Mountains of northern Wyoming. The cave harbors fossils from 150,000 years ago, which scientists have been collecting for research.
“Inside the cave is like a refrigerator,” McGuire says. “The temperature is 40 degrees all year round, so everything preserves beautifully.” In the cave are layers of fossils dating back from 150,000 years to recent times, giving McGuire the opportunity to study how a community changes over long periods.
McGuire is an assistant professor with joint appointment in the Schools of Biological Sciences and of Earth and Atmospheric Sciences. She is using the fossils to understand what types of species fill ecological niches after extinction events and how long it takes populations to normalize after a major transition. Similar extinctions of large mammals are occurring today in Africa and South Asia, according to McGuire. She is using the data to determine what to expect not only from specific extinctions, but also from major ecological disruptions occurring worldwide.
In between field visits to Natural Trap Cave, McGuire outsources the fossil work through Fossil Wednesdays. On Wednesday afternoons, 3-5 PM, during the semester, McGuire’s lab is open to all who are interested in hunting for fossils in the rock samples she brought back from Natural Trap Cave.
“Folks come to Fossil Wednesdays to experience the excitement of making new discoveries, accompanied by dramatic soundtracks playing in the background,” McGuire says. “At the same time, it is a relaxed atmosphere for chatting and really getting your mind off the stresses of the week.”
Through Fossil Wednesdays, McGuire has brought the thrill of discovery-based biology to engineers, business majors, and staff members from across campus and beyond. She has also trained K-12 school teachers to bring the excitement of hypothesis-driven discovery to their students.
The WyomingPBS crew visited the cave in July 2017, according to McGuire. “They filmed us inside the cave and did individual interviews with several of us outside the cave.” In the preview provided by WyomingPBS, McGuire is on camera at the end, holding a fossil. In the documentary itself, McGuire first appears at around 5:15.
WyomingPBS will air the episode on Sunday, Feb. 18, at 9 PM and on Friday, Feb. 23, at 10 PM. It is at wyomingpbs.org and on WyomingPBS’s YouTube Channel after the broadcasts.
EDITOR'S NOTE: This item was revised on Feb. 20, 2018. The documentary was added from YouTube.
The Amazon molly, an all-female fish species, is thriving despite dismal views of the genetic health of asexual vertebrae. The story features a comment from the School of Biological Sciences Pedram Samani's editorial in Nature. Samani writes, "The main finding of the paper is that the species is in remarkably good genomic health."