UC Davis News: Health and Medicine

UC Davis partners in $8.3 million effort to fight childhood malnutrition

Mon, 14 May 2012 16:25:00 -0700

Researchers at the University of California, Davis, will join in an international research effort to develop new ways to diagnose, treat and prevent malnutrition in infants and children around the world.

The Breast Milk, Gut Microbiome and Immunity Project is funded by $8.3 million from the Bill & Melinda Gates Foundation and will be led by the Washington University School of Medicine in St. Louis. UC Davis will receive $1.1 million of the total.

The UC Davis researchers who will participate in the project are nutritionist Kathryn Dewey and microbiologist David Mills.

Severe malnutrition has long been thought to stem simply from a lack of adequate food. But now scientists understand the condition is far more complex and may involve a breakdown in the way gut microbial communities process various components of the diet.

The community of intestinal microbes and its vast collection of genes, known as the gut microbiome, is assembled right from birth and influenced by babies’ early environments and the first foods they consume, such as breast milk.

Through the Breast Milk, Gut Microbiome and Immunity Project, scientists will evaluate the relationship among first foods, the developing community of microbes in the intestine, and the developing immune system.

The new research builds on ongoing clinical studies in Africa, South Asia and South America of malnourished and healthy infants and children and their mothers; the Gates Foundation also funds those studies.

“This multidisciplinary project will allow us to expand our understanding of how to prevent infant malnutrition, which is a major focus of the UC Davis Program in International and Community Nutrition,” Dewey said. “The results of these experiments will provide critical information about whether the lipid-based nutrient supplements that we are evaluating in ongoing research have an influence on the collection of microorganisms in the human gut, which will help us understand the impact of our interventions on child growth."

As director of the International Lipid-Based Nutrient Supplements Project, Dewey is involved with two projects in Malawi that are providing biological samples for the newly funded research consortium. More information about the lipid-based nutrient supplement project is available at: http://ilins.org.

As part of the new project, Mills and his colleagues at the UC Davis Foods for Health Institute will examine the complex, protective sugars in breast milk and characterize specific bacteria in the guts of these infants. The researchers also will look for similar protective sugars in existing dairy products.

“This project will identify specific milk components from commercial dairy streams, which -- in combination with milk-responsive bacteria -- may extend the natural protection of mother's milk past weaning to a fragile population of children who desperately need that protection,” Mills said.

“The opportunity to deliver diet-based solutions in the near term – sourcing from commercial milk operations – is truly exciting, ” he said.

More information about the UC Davis Foods for Health Institute is available at http://ffhi.ucdavis.edu/.

The overall project will be led by Jeffrey I. Gordon at the Washington University School of Medicine in St. Louis.

UC Davis plans 13 commencements, will graduate first nursing students

Tue, 08 May 2012 11:25:00 -0700

Thousands of students from the University of California, Davis, will participate in 13 commencement ceremonies this spring, including the first class from the new Betty Irene Moore School of Nursing.

Commencement season begins Thursday, May 17, and concludes Sunday, June 17.

Guest speakers will include:

Goodwin Liu, an associate justice of the California Supreme Court, at the commencement for the School of Law on May 17;
Marie V. McDemmond, president emeritus of Norfolk State University in Virginia, at the commencement for the School of Education on June 13;
James C. Davis, president of Chevron Energy Solutions, at the commencement for the Graduate School of Management on June 16; and
Secretary General Chris Buijink of the Ministry of Economic Affairs, Agriculture and Innovation for the Netherlands, at the commencements for the College of Agricultural and Environmental Sciences on June 17.

For more about speakers, visit: http://commencement.ucdavis.edu/speakers.html.

Commencement dates, times and locations are as follows:

May 17 — School of Law at 2 p.m. at the Mondavi Center for the Performing Arts;
May 19 — School of Medicine at 10 a.m. at the Mondavi Center;
June 13 — School of Education at 4 p.m. at the Mondavi Center;
June 14 — Graduate Studies at 4 p.m. in the ARC Pavilion;
June 15 — College of Biological Sciences at 9 a.m. in the ARC Pavilion;
June 15 — School of Veterinary Medicine at 10 a.m. at the Mondavi Center;
June 15 — College of Engineering at 3 p.m. in the ARC Pavilion;
June 16 — College of Letters and Science at 9 a.m., 1 p.m. and 5 p.m. in the ARC Pavilion;
June 16 — Graduate School of Management at 10 a.m. at the Mondavi Center; and
June 17 — College of Agricultural and Environmental Sciences at 9 a.m. and 2 p.m. in the ARC Pavilion.

In addition, the Betty Irene Moore School of Nursing will hold a special celebration of its first graduates at 12:30 p.m. on June 14 at the UC Davis Conference Center, before students participate in the Graduate Studies commencement. About 25 nursing students are candidates for a Master of Science degree.

Established in 2009, the nursing school admitted the first students to its master’s and Doctor of Philosophy programs in fall 2010. The school focuses on preparing graduates as educators, researchers and leaders to promote health, advance quality of care and safety, and shape policy.

The School of Law will award 23 Master of Laws and 202 Juris Doctor degrees at its ceremony, and the School of Medicine will award 108 Doctor of Medicine, four Master of Health Informatics and 24 Master of Public Health degrees.

Estimates of degrees to be awarded at the other ceremonies will be available in June. In 2010-11, UC Davis conferred 8,350 degrees.

Tickets are required for all commencement ceremonies except Graduate Studies, and they are distributed to graduating students by individual schools and colleges.

UC Davis will offer live and on-demand webcasts of each of the commencements at http://commencementvideo.ucdavis.edu/.

UC Davis academic associations award prizes for faculty teaching, research, service

Fri, 04 May 2012 15:04:00 -0700

The UC Davis Academic Senate and Academic Federation have announced their 2012 teaching and research prize recipients.

The senate each year presents Distinguished Teaching Awards and Distinguished Scholarly Public Service Awards. The federation honors its members for Excellence in Teaching and Excellence in Research.

ACADEMIC SENATE

Distinguished Teaching Award: Undergraduate

• Frances Dolan, professor, Department of English — Teaching is central in her work and in her own scholarship. Describing her as a “dazzling lecturer” and mentor for students, English professor Margaret Ferguson said: “Whether teaching a course of 200 or mentoring a single MURALS (Mentorships for Undergraduate Research in Agriculture, Letters and Science) student, Fran pays extraordinary attention to the details of pedagogy; she is interested not only in introducing students to new texts, genres and critical questions, but also in strengthening their ability to read closely and to ask big questions of what they read.”

• Ari Kelman, associate professor, Department of History — He shines at the front of a lecture hall in a way that few others do, said David Biale, professor and chair, Department of History. “Working largely without notes, responding frequently to student questions without losing the thread of his own thought, he proceeds through a lecture, crafting a clear narrative and analysis as he goes along.” He added: “While he sometimes ventures into theater — his lecture on the caning of Sen. Charles Sumner is legendary — students appreciate his lectures most for their combination of sophistication and accessibility.”

• David Osleger, lecturer, Department of Geology — He has “an exceptional ability to get students involved in the course material,” his faculty colleagues wrote in nominating him. In evaluating his classes, students use words like “fascinating,” “fun” and “enlightening.” For many students, taking a general education geology class from Osleger led them to either take more geology classes, or to become geology or natural sciences majors. Osleger also is committed to recruiting students, especially from underrepresented groups, into natural sciences and geology, and mentoring undergraduates on career choices in geological sciences.

• Jay Stachowicz, associate professor, Department of Evolution and Ecology — He is a motivator, engaging and entertaining in the classroom, and “an incredible mentor,” encouraging students to participate in his lab. “He teaches students more than just the skills needed to run different marine ecology experiments,” Natalie Caulk, Elise Hinman and Kristen Kelley wrote in a nomination letter. “He teaches the process of scientific inquiry.” Faculty colleagues Artyom Kopp and Rick Grosberg said Stachowicz’s research experience energizes all of his classes: “His teaching embodies all that a great research university stands for.”

Distinguished Teaching Award: Graduate and Professional

• Richard Sexton, professor and chair, Department of Agricultural and Resource Economics — He is a master of his subject matter, communicates well and is remarkably adept at maximizing classroom participation. In addition, he has played an integral role in curriculum development, especially earning praise for master’s-level macroeconomic theory, which he began teaching in 1994 and later expanded into a two-course sequence. Those courses now attract students from many other disciplines. Sexton pioneered the incorporation of industrial organization concepts into instruction on agricultural market analysis.

• Richard Tucker, professor of cellular biology and human anatomy, School of Medicine — He is the primary instructor for the single largest course in the four-year curriculum: “Gross, Radiologic and Developmental Anatomy,” which includes foreign terminology and physically demanding laboratory sessions. Students laud his caring and motivational style, “fantastic ability to present a large amount of developmental information in a short period of time,” and his knowledge of the material, which he “can explain at any level of detail the moment demands.”

Distinguished Scholarly Public Service Award

• Liz Applegate, senior lecturer, Department of Nutrition — She puts as much effort into public service as she does to her teaching, notably Nutrition 10, which draws rave reviews, owing to her philosophy of making nutrition and fitness education actionable and pertinent. Off campus, she gives countless lectures and workshops to a broad range of community groups, particularly those comprising underrepresented populations — people who are disabled or chronically ill, for example. She also works with state and national organizations, and youth sport groups. In addition, she is a valuable resource for the media.

• John Largier, professor, Department of Environmental Science and Policy, and the Bodega Marine Laboratory — He has played a notable and sustained role in service to the public by providing scientific advice on matters related to the health of marine and coastal environments via media events and interviews, membership on assessment and advisory teams, participation in working groups and on task forces, and presentations at public meetings. His efforts are across the spectrum from service intended to spur development of science beyond the university, to the application of science in policy, advising agencies and informing the public.

• Mark J. Mannis, professor and chair, Department of Ophthalmology and Vision Science, and director, Eye Center — Recognized for his efforts to increase the number of high-quality ocular tissues available for transplant, as well as the number of ophthalmologists and technicians trained in the latest corneal transplant and eye-banking methodologies — thus restoring sight for tens of thousands of people with blinding diseases around the globe. Starting 30 years ago, Mannis and the UC Davis Medical Center turned the Lions Club’s fledgling eye bank into the well-established Sierra Eye and Tissue Donor Services.

• Robert K. Washino, emeritus professor, Department of Entomology — Throughout his academic career and now in retirement, he gives freely of his time and expertise to local, state, federal and international agencies, as well as the private sector. He served on U.S. Department of Agriculture and California Department of Food and Agriculture task forces targeting such insects as the Africanized honeybee and Mediterranean fruit fly. He added breadth and depth to such organizations as the Entomological Society of America and the World Health Organization.

ACADEMIC FEDERATION

Excellence in Teaching

• Eric Mann, lecturer, Department of Microbiology — His faculty colleagues said he is enthusiastic about his teaching and strives to stimulate his students to think independently. In their evaluations, students praise his clear lecture style, meticulous organization and remarkable sense of humor. His extensive work in curriculum development included a revamp of introductory microbiology to meet the needs of preprofessional students, and a reorganization of the MIC 101 labs so they could be offered in the summer. His dedication is astounding, said his colleagues, noting that he supervises lab instruction 18 hours a week in a typical quarter.

• John Rundin, lecturer, Classics Program — He is described as being abundantly generous to students inside the classroom and out, keeping an open door for those in need of assistance in one of the most difficult subjects: Latin. “His office is next to mine, so I can hear him patiently explaining Latin forms or grammar — never losing his sense of compassion and his conviction that every student can grasp the language — and also offering encouragement and advice,” wrote Emily Albu, associate professor and Classics Program director. “I see the academic results in the number of students who continue to a classics major or minor.”

Excellence in Research

• Wei Yao, assistant adjunct professor, School of Medicine — Her most recent work, published in Nature Medicine earlier this year, involved the development of a novel technique (using the molecule LLP2A-Ale) to enhance bone growth — offering a potential treatment for osteoporosis. Nancy E. Lane, who holds the Endowed Chair in Healthy Aging and Geriatric Medicine, said Yao has made a number of seminal scientific discoveries at UC Davis. “The scope of inquiry, the importance of the topic matter, the methodical construction of a unified approach to the questions and the gratifying results all speak for themselves,” Lane said.

Biomedical researchers receive Hartwell Foundation awards

Tue, 01 May 2012 11:00:00 -0700

Two faculty members from the University of California, Davis, are among 12 scientists selected to receive Individual Biomedical Research Awards from The Hartwell Foundation this year. The awards provide $100,000 of direct support each per year for three years, as well as videoconferencing equipment for periodic communications with the foundation and other award recipients. The foundation is also funding a UC Davis Hartwell Foundation postdoctoral researcher with $50,000 per year over two years.

The awardees are: Frederic Chedin, associate professor in the Department of Molecular and Cellular Biology, College of Biological Sciences; Noriko Satake M.D., assistant professor of pediatrics in the UC Davis School of Medicine and Comprehensive Cancer Center; and Paula Goines, postdoctoral researcher in the Department of Molecular Biosciences in the UC Davis School of Veterinary Medicine.

In 2011, The Hartwell Foundation designated UC Davis as one of its Top Ten Centers for Biomedical Research. Including Chedin and Satake, the foundation has made Individual Biomedical Research Awards to five UC Davis scientists and engineers since 2009.

The prestigious designation in 2012 also meant that UC Davis received a Hartwell Fellowship to fund one postdoctoral researcher, chosen by the university, who exemplifies the values of the foundation. The fellowship award is intended to support scientists in the early stages of biomedical research careers by enabling them to pursue further specialized training. Goines is the first fellowship recipient from UC Davis.

“The foundation is impressed with the manner in which UC Davis has embraced the Hartwell process to inspire innovation and achievement. UC Davis' leadership exceeded our expectations by their collegial participation to identify outstanding proposals from interested faculty and win two awards this year,” said Fred Dombrose, president of The Hartwell Foundation.

Chedin will use the funds to explore a novel approach to understanding a common autoimmune disease, systemic lupus erythematosus, in which the body's immune system attacks itself, including making antibodies against DNA.

At any time, most of our DNA is "silenced" or switched off by a chemical modification, except at a few specific sites, called CG islands, which serve as “on” switches for our genes. Chedin's lab has been studying how these CG islands are protected from silencing; he thinks that too little silencing might play a role in the development of systemic lupus.

He will test his hypothesis by using as a model system the severe but rare autoimmune disorder called Aicardi-Goutières syndrome, which mimics early onset lupus. The syndrome affects infants, and in most cases leads to death by age 10 to 15. Understanding the biological mechanisms that underlie Aicardi-Goutières will generate critical insights into how the innate immune system can be triggered. If Chedin is successful, his efforts will lead to the development of new diagnostic tests and therapies for children affected with early onset lupus and related autoimmune diseases.

Satake is working to develop a new method to treat childhood leukemia, called molecular targeting. The approach is different from conventional chemotherapy drugs, which kill healthy blood cells and leukemic cells equally. Satake proposes to develop a unique method to deliver a type of molecule that interferes with gene expression, called siRNA. She seeks to deliver it specifically to the leukemia cells, but not to normal healthy cells. If she is successful, her narrow-target approach could prove a transformative pediatric cancer treatment.

Satake explained that while considerable gains have been made in curing pediatric cancers, there are still lethal forms of the disease that resist treatment.

“Even when we cure the cancer, many of those patients are known to have significant long-term side effects or late effects derived from radiation and chemotherapy that can cause heart failure, osteoporosis, learning disabilities and even secondary cancer,” she said. “Unfortunately, those are irreversible. The new targeted therapy to be developed will not only be more effective in treating cancers but also have fewer side effects to normal cells than current therapies.”

Goines is a recent Ph.D. graduate from UC Davis. She will work with Pamela Lein, professor of neurotoxicology in the Department of Molecular Biosciences, on a new approach to studying autism by looking at nerve cells grown from adult stem cells present in the hair follicles of patients.

In the Hartwell competition, all nominees submit a detailed research proposal, are personally interviewed and make a formal presentation of their proposed research. In selecting awardees, The Hartwell Foundation takes into account the nature of the proposed innovation, the extent to which a strategic or translational approach might promote rapid clinical application of research results, the supportive role and extent of collaboration in the proposed research, the institutional commitment to provide encouragement and technical support to the investigator, and the extent to which funding the investigator will make a difference.

Genomes of two champion bulls sequenced

Tue, 24 Apr 2012 10:49:00 -0700

With more than 60,000 descendants in six generations, Pawnee Farm Arlinda Chief and his son Walkway Chief Mark cast a long genetic shadow. New research on the genomes of the two bulls show how portions of their DNA that control important traits such as disease resistance or milk production have spread throughout the contemporary Holstein breed, the world’s highest-producing dairy animal.

The research, published online April 23 in Proceedings of the National Academy of Sciences, may provide for faster and less costly methods to breed genetically elite cattle.

"The technique we developed, called ‘haplotracking,’ allows researchers to identify chromosome segments that are under selection in a certain population and match them with genes controlling specific traits," said Harris Lewin, senior author of the paper, who led the research project while at the University of Illinois Urbana-Champaign. Lewin is now vice chancellor for research at the University of California, Davis.

The cattle genome research offers a window into evolution, showing how selection affects genes that control complex traits like resistance to infectious diseases, Lewin said.

Chief, born in 1962, and Mark, born in 1978, each account for about 7 percent of the genomes of the current North American Holstein cow population, according to research published previously by the U.S. Department of Agriculture. The new study allows researchers to track specific genes in the population.

"These were two of the greatest bulls in the history of the Holstein breed," Lewin said.

Lewin and his colleagues sequenced the genomes of both bulls, identifying more than one million single-nucleotide polymorphisms. These changes, known as SNPs, occur when a single letter of the genetic code is changed. The researchers used this information to identify haplotypes, or stretches of DNA, that Chief and Mark had passed down to their descendants intact.

Within these haplotypes, the researchers identified genes and SNPs related to fertility, milk yield and virus resistance – all traits that could potentially and significantly augment the economic viability of a dairy cattle-breeding operation or dairy farm.

Dairy cattle have been under intense selection for economically important traits such as milk yield and milk fat for more than a half-century, resulting in large databases of production data and DNA samples – much more information than is available for human populations. The comparative wealth of genetic information about cattle, especially the ability to reconstruct and track individual haplotypes, may prove vital in understanding the genetic basis for complex traits in both human and other animal populations, Lewin said.

The first author of the paper is Denis Larkin of the Department of Animal Sciences at University of Illinois Urbana-Champaign, now at Aberystwyth University in the United Kingdom. In addition to Lewin, other authors include: Hans Daetwyler, Mike Goddard, Iona Macleod and Ben Hayes at the Department of Primary Industries, Victoria, Australia; and other researches at UIUC; the University of Melbourne, Australia; La Trobe University, Australia; Roche Inc., Indianapolis; and 454 Life Sciences, Branford, Conn. The research was partly supported by the U.S. Department of Agriculture.

UC Davis dean elected to Johns Hopkins Society of Scholars

Tue, 17 Apr 2012 14:30:00 -0700

Immunologist James Hildreth, dean of biological sciences at the University of California, Davis, has been elected to the Johns Hopkins Society of Scholars.

Hildreth, a leading AIDS researcher, came to UC Davis in 2011 upon his appointment as dean. He left Tennessee’s Meharry Medical College, where he was a professor and director of the Center for AIDS Health Disparities Research.

Before that he served on the faculty of the Johns Hopkins School of Medicine, where he began his research on HIV, the virus that causes AIDS.

His work at Johns Hopkins University qualified him for the Society of Scholars. Established in 1967, it includes former postdoctoral fellows, postdoctoral degree recipients, house staff, and junior or visiting faculty who served for at least one year at Johns Hopkins and later gained marked distinction in their fields of physical, biological, medical, social or engineering sciences, or in the humanities.

Hildreth earned a bachelor’s degree from Harvard in 1979; his doctorate in immunology from Oxford in 1982, as a Rhodes scholar; and his medical degree from Johns Hopkins in 1987.

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Newly awarded fellowships are supporting a half-dozen University of California, Davis, faculty members in their research and writing.

Simons Foundation fellowships went to Anne Schilling, professor, and Dan Romik, associate professor, both of the Department of Mathematics; and Warren Pickett, professor of physics.

The awards provide support to extend academic leaves for up to a year, allowing recipients to focus solely on research.

The American Council of Learned Societies is supporting three faculty members in their book projects on medieval French farces, Mark Twain and human rights in the Middle East. The recipients:

• Noah Guynn, associate professor, Department of French and Italian, who is writing The Many Faces of Farce: Ethics, Politics, and Urban Culture in Late Medieval and Early Modern France, challenging assumptions that such farces were used to entertain the masses while reconciling them to lives of subservience. Instead, Guynn reveals evidence of cultural resistance and political risk in the genre.

• Hsuan L. Hsu, professor, Department of English, who is writing Sitting in Darkness: Mark Twain and America’s Asia. Hsu describes it as “the first book-length study of Mark Twain’s responses to trans-Pacific historical phenomena such as Chinese immigration, diplomatic relations with China, the annexation of Hawaii and the U.S. regime in the Philippines.”

• Keith David Watenpaugh, associate professor, Department of Religious Studies, who is writing Bread from Stones: The Middle East and the Making of Modern Humanitarianism, the first major study of the history of human rights and international humanitarianism in the Middle East.

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Professor John Eadie of the University of California, Davis, has been honored for his waterfowl conservation efforts.

The waterfowl biologist, affiliated with the Department of Wildlife, Fish and Conservation Biology, received the awards at the 77th North American Wildlife and Natural Resources Conference.

Ducks Unlimited presented a Wetland Conservation Achievement Award, commending Eadie for his research on food resources for migrating ducks in the Central Valley’s seasonally flooded wetland and rice land — data that contributed to a conservation model for these critical wintering grounds.

Eadie received the National Blue-Winged Teal Award from the North American Waterfowl Management Plan, a joint project of the United States, Canada and Mexico.

Eadie, who runs the Avian Conservation and Ecology Lab, joined UC Davis in 1995 as the first holder of the Dennis G. Raveling Professorship.

•••

Composer-musician Kurt Rohde of the faculty at the University of California, Davis, has scored two commissions and two residencies.

One commission is from the Lydian String Quartet at Brandeis University, and the other is from the independent and nonprofit Meet the Composer, part of New Music USA. For the latter, Rohde is collaborating on a work for small ensemble, with narrator and projected images.

Rohde’s residencies will be at the Radcliffe Institute for Advanced Study at Harvard University, where he will work on the chamber opera projects during the 2012-13 academic year; and the Montalvo Arts Center, Saratoga (Santa Clara County), where, during the summers of 2013 and 2014, he will collaborate on a film project.

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With a swearing-in ceremony in Washington, D.C., physics professor Robin Erbacher of the University of California, Davis, officially became a member of the federal government’s High Energy Physics Advisory Panel.

It advises the government on research in theoretical and experimental physics, reporting jointly to the Department of Energy and the National Science Foundation.

Erbacher earned her doctorate from Stanford University and joined the UC Davis faculty in 2004. She is a member of the Compact Muon Solenoid experiment at the Large Hadron Collider near Geneva, Switzerland.

•••

Professor Laura Marcu of the University of California, Davis, has been elected a fellow of the professional organization SPIE, in recognition of her achievements in biomedical optics.

For example, she developed handheld probes for identifying the edges of tumors during surgery, and probes that can be inserted through catheters to investigate atherosclerotic plaques in heart disease.

SPIE began in 1955 as the Society of Photographic Instrumentation Engineers, and has changed names twice. It is now known simply as SPIE, the international society for optics and photonics.

•••

Nancy McTygue, executive director of the California History-Social Science Project, based at the University of California, Davis, has taken a seat on the California Instructional Quality Commission, by appointment of the state Board of Education.

The Instructional Quality Commission, known as the Curriculum Commission up until Jan. 1, 2012, serves in an advisory capacity to the state board, on issues related to kindergarten through grade-12 curriculum and instruction.

This is McTygue’s forte. The only panel member with a university-affiliated post, she oversees seven regional sites, each a collaborative of teachers (kindergarten through four-year college) and scholars dedicated to improving history and social science curriculum and instruction in the state’s schools.

The sites range from the UCI History Project at UC Irvine in the south, to The History Project at UC Davis in the north.

Scientists discover tool that uncrosses chromosomes

Thu, 12 Apr 2012 15:00:00 -0700

Researchers at the University of California, Davis, have discovered a key tool that helps sperm and eggs develop exactly 23 chromosomes each. The work, which could lead to insights into fertility, spontaneous miscarriages, cancer and developmental disorders, is published April 13 in the journal Cell.

Healthy humans have 46 chromosomes, 23 from the sperm and 23 from the egg. An embryo with the wrong number of chromosomes is usually miscarried, or develops disorders such as Down syndrome, which is caused by an extra copy of chromosome 21.

During meiosis, the cell division process that creates sperm and eggs, matching chromosomes pair up and become connected by “crossing over” with each other, said Neil Hunter, a professor of microbiology at UC Davis and senior author of the new study.

These connections are essential for precise chromosome sorting and the formation of sperm and eggs with exactly the right numbers of chromosomes. Crossovers also play a fundamental role in evolution by allowing the chromosomes to swap chunks of DNA, introducing some variety into the next generation.

Each pair of chromosomes must contain at least one crossover. But there shouldn’t be more than about two crossovers per pair, or the genome could be destabilized.

In their paper, Hunter and his colleagues describe a “missing tool” that explains how crossovers are regulated.

"There must be enzymes that ensure at least one crossover, but not too many," said Hunter, who is also a member of the UC Davis Comprehensive Cancer Center research program.

Hunter, graduate students Kseniya Zakharyevich and Shangming Tang, and research associate Yunmei Ma looked for enzymes that could cut DNA to form crossovers in yeast, which form sexual gametes, or spores, in much the same way that humans and other mammals form sperm and eggs.

"There were several good candidates, but none turned out to play a major role," Hunter said.

Then they discovered the missing tool for crossing over: three yeast enzymes, Mlh1, Mlh3 and Sgs1, which work together to cut DNA and make crossovers.

It turns out that the human equivalents of these enzymes are well known for their role in suppressing tumors. Human MLH1 and MLH3 are mutated in an inherited form of colon cancer. BLM, the human equivalent of Sgs1, is mutated in a cancer-prone disease called Bloom’s syndrome.

“Sgs1 was the biggest surprise,” Hunter said. “We previously knew it as an enzyme that unwinds DNA to prevent crossovers. Its role in making crossovers had been hidden by other enzymes that can step in when it is absent.”

"While other enzymes cut DNA randomly, Mlh1-Mlh3-Sgs1 only makes crossovers. This unique activity is essential for meiosis and its discovery is a huge step forward," he said.

The work was supported by the National Institutes of Health. Hunter is an early career scientist of the Howard Hughes Medical Institute.

Leadership for BGI@UCDavis appointed

Mon, 09 Apr 2012 10:15:00 -0700

Bart Weimer, a professor in the Department of Population Health and Reproduction in the UC Davis School of Veterinary Medicine, and Hao Zhang, chief operating officer of BGI Americas, have been appointed co-directors of BGI@UCDavis, a partnership between UC Davis and BGI, the world's largest genome sequencing organization.

Weimer and Zhang will be responsible for the day-to-day operations of the center, to be located on UC Davis' Sacramento campus.

"Professor Weimer brings a wide range of experience both in genomic science and industry partnerships to this role. This exciting joint venture will benefit greatly from his leadership," said Harris Lewin, vice chancellor for research at UC Davis.

The center will be managed by a steering committee, of which Weimer and Zhang will be members, and a governance committee. The two committees will include both UC Davis and BGI personnel, consistent with the closely collaborative nature of this partnership.

The co-directors will also act as liaisons to their respective institutions to develop projects and look for opportunities to bring BGI's capabilities to bear on scientific problems and challenges in areas including human and animal health, agriculture and the environment.

Weimer joined the faculty at UC Davis in 2008 from Utah State University, where he was director of the Center for Integrated BioSystems, which provided core biotechnology services to the campus and conducted genomic science research. He earned his bachelor's degree from the University of Arizona and his Ph.D. from Utah State, and completed postdoctoral training at the University of Melbourne, Australia. He has worked in both academia and the private sector, including three startup companies based on technology developed in his lab.

In his research, Weimer uses functional genomic techniques to study microbial systems biology, especially of bacteria that can cause foodborne illness.

Zhang was born and educated in China. After he received his bachelor's degree from Peking University, he moved to the U.S., where he earned his Ph.D. degree from The Ohio State University in 2007. He joined Cambridge, Mass.-based BGI Americas in 2010 as an application biologist before becoming the organization’s chief operating officer. As co-director of BGI, he will be based in Sacramento.

Through BGI, campus researchers will have access to the capabilities and expertise of one of the world’s premier genomics and bioinformatics institutes, while BGI researchers will have the ability to collaborate with UC Davis researchers, thereby benefiting from the university’s diverse resources and expertise, especially in biology, medical sciences, agriculture, the environment and education.

An interim facility with three DNA sequencing machines began operations in renovated space on the Sacramento campus at the end of 2011. The eventual facility, once completed, will house up to 20 such machines. Renovation and construction of the new facility should be complete by end 2012.

3 from UC Davis are new fellows of the American Academy of Microbiology

Wed, 14 Mar 2012 00:00:00 -0700

Three professors at the University of California, Davis, are among the newest class of fellows in the American Academy of Microbiology:

• Patricia Conrad — Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine.

• Jonathan Eisen — Department of Medical Microbiology and Immunology, School of Medicine, and Department of Evolution and Ecology, College of Biological Sciences. He is also affiliated with the Genome Center and the Center for Population Biology.

• Wolf Heyer — Departments of Microbiology, and Molecular and Cellular Biology, College of Biological Sciences. He is also affiliated with the Cancer Center.

The academy describes itself as the honorific leadership group within the American Society for Microbiology, the world’s oldest life science organization.

Peer voting determines who gets in to the academy, based on the candidates’ scientific excellence, originality and leadership; high ethical standards; and scholarly and creative achievement.

The academy then calls upon its membership for authoritative advice and information on critical issues in microbiology, from responding to congressional inquiries to organizing meetings and workshops.

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James Sanchirico, a natural resource economist at the University of California, Davis, has been named the 2012 recipient of the Rosenstiel Award in Oceanographic Science.

Sanchirico received a doctorate in agricultural and resource economics at UC Davis and later joined the faculty of the Department of Environmental Science and Policy.

He applies quantitative methods to study the design and evaluation of policy instruments aimed at conserving natural resources. His ocean-related research takes in marine population and habitat management, and the design of market-based policies, such as fishing quota systems.

His website lists the following among the projects that he is working on at this time: bioeconomic analysis of stellar sea lion conservation, and coral reef and mangrove management.

He serves the National Research Council as a member of two new committees, one that is reviewing the National Ocean Acidification Research Plan and one that is evaluating the effectiveness of stock rebuilding plans in the 2006 Fishery Conservation and Management Reauthorization Act.

The University of Miami’s Rosenstiel School of Marine and Atmospheric Science administers the award, with support from the Rosenstiel Foundation. A school spokeswoman said the award (including a $10,000 prize) will be presented to Sanchirico during a dinner April 24.

And, while visiting the school, Sanchirico will deliver one or two lectures, the spokeswoman said.

•••

Mathematics professor Naoki Saito of the University of California, Davis, has been elected to a two-year term as vice chair of the Activity Group on Imaging Science of the Society for Industrial and Applied Mathematics.

Saito is chair of the Graduate Group in Applied Mathematics.

His own studies take in such topics as harmonic analysis, signal processing, image analysis, data analysis and compression, pattern recognition and human and machine perception.

Expert on youth football head injuries to speak

Mon, 05 Mar 2012 00:00:00 -0800

Thursday, March 8 -- Stefan Duma, a national expert on concussion, will talk about his work on head impacts in youth football at 4 p.m. in Room 1005 of the Genome and Biomedical Sciences Facility at the University of California, Davis.

Duma is professor and department head at the Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences and director of the Center for Injury Biomechanics.

Duma's research on head impacts in second-graders playing youth league football has received wide attention. His group found high-level impacts in both practices and games, and made recommendations to reduce serious head impacts in practices.

Duma's talk is part of the Department of Biomedical Engineering’s Distinguished Seminar Series.

Miniature pressure sensors for medical touch

Mon, 05 Mar 2012 00:00:00 -0800

A new kind of flexible, transparent pressure sensor, developed at the University of California, Davis, for use in medical applications, relies on a drop of liquid.

The droplet goes in a flexible sandwich of the substance polydimethylsiloxane, or PDMS. The sensor acts as a variable electrical capacitor. When the sensor is pressed down, the sensing droplet is squeezed over conductive electrodes, increasing its capacitance.

“There’s a huge need for flexible sensors in biosensing,” said Professor Tingrui Pan, who led the research project.

He and his colleagues used the sensor successfully in measuring the pulse in the human neck. The sensor also could be used in “smart gloves,” giving physicians an enhanced ability to measure the firmness of tissues and detect tumors, and in “smart contact lenses,” to monitor intraocular pressure without affecting vision.

Pan’s research paper — for which graduate students Baoqing Nie and Siyuan Xing and ophthalmology professor James Brandt served as co-authors — appeared in the December issue of the journal Lab on a Chip.

The National Science Foundation gave partial support to the project.

R-loops break walls of gene silencing

Thu, 01 Mar 2012 00:00:00 -0800

Researchers at the University of California, Davis, have figured out how the human body keeps essential genes switched “on” and silences the vast stretches of genetic repeats and “junk” DNA.

Frédéric Chédin, associate professor in the Department of Molecular and Cellular Biology, describes the research in a paper published today (March 1) in the journal Molecular Cell. The work could lead to treatments for lupus and other autoimmune diseases, by reversing the gene-silencing process known as cytosine methylation.

“R-loops” are the key, say graduate student Paul Ginno, Chédin and colleagues. The loops emerge in the RNA transcription process in DNA sections that are rich in cytosine and guanine, the C and G in the four-letter DNA code. These C and G stretches serve as “on” switches, or promoters, for about 60 percent of human genes.

Scientists have known since the 1980s that these so-called CG island promoters are not subject to methylation. But, Chédin said, the mechanism has been a long-standing mystery.

The UC Davis researchers built a catalog of almost 8,000 CG islands in the human genome, studied their DNA sequences and found the CG sequences to be skewed toward having one strand of the double helix rich in guanine, and the complementary strand rich in cytosine.

Then, in RNA transcription, the G-rich RNA remains stably bound to a C-rich DNA strand, forcing the G-rich DNA strand into a loop — which then prevents methylation.

DNA methylation is considered part of the new field of epigenetics, which studies inheritable genetic changes that are not directly coded in the DNA sequence. However, the new work shows that, at least at CG islands, the epigenetic state is determined by the DNA sequence.

Scientists know that reduced methylation of DNA plays a key role in triggering autoimmunity in lupus, Chédin said. However, the molecular events behind this DNA under-methylation have been unclear.

“Our work establishes that excessive R-loop formation may drive under-methylation and autoimmunity,” Chédin said.

Co-authors: Paul Lott, graduate student; Holly Christensen, undergraduate; and Ian Korf, associate professor in the Department of Molecular and Cellular Biology and the Genome Center.

The National Institutes of Health and the Foundation for Prader-Willi Research supported the project.