Lirong Zeng presents next seminar

Photo of Dr. Lirong Zeng

Lirong Zeng, assistant professor in the UNL Department of Plant Pathology will present "Pseudomonas syringae Effector AvrPtoB Exploits A Plant Defense Essential Subset Of Ubiquitin-Conjugating Enzymes To Suppress Host Immunity," Oct. 12 in VBS 145 at 4 p.m.

Unlike vertebrates, plants are sessile and do not possess an adaptive immune system. Nevertheless, plants have evolved a sophisticated innate immune system to protect them from many attempted pathogen infections. To subvert plant immune responses, the bacterial pathogen Pseudomonas syringae pv. tomato (Pst) delivers through a type III secretion system about 30 effector proteins into the host cell. One of the effectors, AvrPtoB, encodes a modular protein where the C-terminal region is a ubiquitin ligase (E3). AvrPtoB can suppress both pathogen/microbe-associated molecular pattern-triggered immunity (PTI) and effector-triggered immunity (ETI) of plant to promote the virulence of Pst, of which the latter is dependent on its C- terminal E3 activity. However, the ubiquitin-conjugating enzyme(s) (E2) that work with AvrPtoB C- terminal E3 in suppressing plant ETI have not been discovered to date. In this study Zeng has identified and cloned 40 tomato genes putatively encoding E2 proteins. Thioester assays indicated the majority of the identified genes encode active E2 enzymes. Phylogenetic analysis classified the 40 tomato E2 enzymes into 13 groups, of which only members of the group III were found to work with AvrPtoB and the plant immunity-associated E3, PUB13, to catalyze ubiquitination. Knocking down of the group III E2 genes in Nicotiana benthamiana plants diminished AvrPtoB-promoted degradation of Fen and the suppression of ETI-associated programmed cell death by AvrPtoB and resulted in decreased plant PTI thus enhanced the growth of the Pst. Knocking down of the group III E2 genes also increased flg22-induced callose deposition as a result of that silencing of group III E2 genes compromised the role of PUB13 in attenuating FLS2-mediated immune signaling. Thus, by exploiting a group of host E2s that are essential for plant defense, AvrPtoB has evolved a strategy for suppressing host immunity that would be difficult for plant to thwart.

Gary Rupp Inducted into Cattle Production Veterinarian Hall of Fame

Photo of Dr. Jenks Britt and Dr. Gary Rupp
Dr. Jenks Britt (left) and Dr. Gary Rupp (right) were recent inductees into the Cattle Production Veterinarian Hall of Fame

Dr. Gary Rupp, veterinarian, UNL emeritus professor and founding director of the Great Plains Veterinary Educational Center, was one of two veterinarians elected to the Cattle Production Veterinarian Hall of Fame at the American Association of Bovine Practitioners Annual Conference in September.

The Cattle Production Veterinary Hall of Fame honors the traditions of production veterinary medicine and the individuals who have made a lasting impact on the profession. Rupp and fellow inductee Dr. Jenks Britt were chosen by their peers from a group of six beef and dairy veterinarian nominees.

“The beef and dairy industries have been fortunate to benefit from the wisdom and advancements provided by these two remarkable veterinarians,” said Brent Meyer, D.V.M., beef cattle technical services, Merck Animal Health. “From the K-R Spay device designed by Dr. Rupp, to the Bov Eq Embryo Transfer Service developed by Dr. Britt, the innovations from these two men have significantly advanced beef and dairy cattle management and bovine reproduction.”

Rupp received his D.V.M. from Colorado State University in 1964. He spent two years teaching at the University of California-Davis, then moved to Meeker, Colorado to enter private practice. After eight years in practice, he left to pursue an opportunity to study ruminant nutrition and reproduction at Colorado State University in outpatient teaching. In 1983, Rupp accepted a position as associate professor at Texas A&M University in Beef Cattle Herd Health. In 1988 he came to Nebraska and was instrumental in the formation of the Great Plains Veterinary Educational Center (GPVEC). He served as GPVEC director for 22 years. Since retiring from the university in 2010, Rupp has operated a seedstock Angus operation in Oak, Nebraska.

With others, Rupp initiated the Cow-Calf Computerized Herd Health-Management Record System and was actively involved in the development of the Kimberling-Rupp Spay instrument. Along with the faculty at GPVEC, he also designed and implemented a variety of clinical teaching programs and began the Beef Cattle Production Management Series. Rupp has been a member of numerous state and national veterinary and beef cattle organizations.

“Receiving this honor is a deeply humbling experience, as I have not totally convinced myself that I measure up,” said Rupp. “I feel very fortunate to have spent most of my life working with and learning from livestock producers, veterinary practitioners, and others to make livestock production as good as it can be. I have always been impressed with the emotional connection those who work in the cattle industry have for the animals and environment.”

The Cattle Production Veterinary Hall of Fame is sponsored by Merck Animal Health, the American Association of Bovine Practitioners, the Academy of Veterinary Consultants, Bovine Veterinarian magazine and Osborn Barr.

For more, watch a video interview with Dr. Rupp at the Bovine Veterinarian website.

Duoyi Hu to Present Oct. 5 Seminar

Photo of Duoyi Hu

Duoyi Hu, graduate research assistant in the School of Veterinary Medicine and Biomedical Sciences, will present a seminar tiltled "HIV-1 envelope-based immunogen design: gp120 outer domain (OD) and gp41 membrane proximal external region (MPER)" on Oct. 5. The seminar will be held in 145 VBS at 4 p.m.

Epitope-based immunogen design is a strategy based on the precise structural relationship between an antigen and its antibody. This approach consists of designing a minimal fragment of an epitope to be presented to the immune system in order to elicit similar neutralizing antibodies. Gp120 outer domain (OD) is a relatively stable domain compared to the inner domain and bridging sheet at the CD4-binding site for the HIV-primary receptor. The potent neutralizing antibodi VRC01 is found to mainly bind to the outer domain. Therefore, the outer domain has been considered as an immunogen candidate for vaccine design. The membrane proximal external region (MPER) of gp41 is a critical region for broadly neutralizing antibody targeting, and there are several broadly neutralizing antibodies found to bind to this region, such as 2F5, 4E10 and Z12e1 etc. However, previous studies showed weakly responses to the naive gp120 outer domain and gp41 membrane proximal external region. In this project, Hu used structure-based design to stabilize these two epitope-based immunogens by introducing disulfide bonds and other amino acid mutations. These immunognes were prepared and injected into guinea pigs to test the immunogencity. The immune responses and neutralization data aginst HIV infection from these immunized animals' antisera will be presented and discussed.

Fellowship awarded to two SVMBS graduate students

Photo of  Rakesh Basavalingappa and Govardhan Rathnaiah
Rakesh Basavalingappa (left) and Govardhan Rathnaiah (right)

Congratulations to Rakesh Basavalingappa and Govardhan Rathnaiah, recipients of the Widaman Distinguished Graduate Fellowship Award!

The fellowship is awarded to outstanding graduate students whose research is related to agriculture. Rakesh is a PhD student focusing on immunology in the lab of Dr. Jay Reddy, and Gov is a PhD student focusing on microbiology in the lab of Dr. Raul Barletta.

A luncheon to honor all those receiving graduate fellowships will be held at the Nebraska East Union on Tuesday, Oct. 13, 2015.

The Widaman Trust was established in 1975 through a generous gift provided to the University of Nebraska Foundation by Mrs. Blanch Widaman.

Congratulations, graduates!

Photo of Prageeth and Moxley
Prageeth and his graduate supervisor Dr. Moxley in their lab.

Congratulations to School of Veterinary Medicine and Biomedical Sciences graduate students Anshuman Das and Prageeth Rukshan Wijemanne who will receive doctoral degrees on Saturday, August 15, 2015.

Prageeth Rukshan Wijemanne will receive a PhD in Integrative Biomedical Sciences. His dissertation title is "Secretion of heat-labile enterotoxin by porcine-origin enterotoxigenic escherichia coli and relation to virulence."

Photo of Dr. Asit Pattnaik and Anshuman Das
Dr. Asit Pattnaik and Anshuman at the SVMBS entrance. Dr. Pattnaik was Anshuman's graduate supervisor.
Anshuman Das will receive a PhD in Integrative Biomedical Sciences with a specialization in virology. Anshuman's dissertation title is "Role of interferon stimulated genes in regulation of the innate antiviral response during vesicular stomatitis virus infection." Anshuman will continue as a post-doctoral fellow at UNL for a brief time before going to the University of North Carolina at Chapel Hill to continue his research, focusing on immunology, under the guidance of Dr. Stanley Lemon.

SVMBS wishes Prageeth and Anshuman all the best in their careers!

Great Plains Veterinary Educational Center Celebrating 25 Years

Photo of GPVEC Bill Krejci Building
Bill Krejci Building at Great Plains Veterinary Educational Center

The Great Plains Veterinary Educational Center (GPVEC) is celebrating 25 years of providing advanced education in food animal production management to veterinary students and practicing veterinarians. To celebrate the anniversary, a reception is scheduled from 1 p.m. to 3:30 p.m. at the Bill Krejci Building at GPVEC, 820 Road 313.

 Institute of Agriculture and Natural Resources Vice Chancellor Ronnie Green,  GPVEC founding director Gary Rupp, and current director Dale Grotelueschen will speak. Tours of the building will be available.

The Great Plains Veterinary Educational Center was established as part of a cooperative agreement between UNL and Kansas State University College of Veterinary Medicine. One provision of the agreement was that UNL would construct and staff a teaching facility at the federally run U.S. Meat Animal Research Center and provide food animal medicine education to KSU veterinary students as part of the fourth-year clinical training curriculum. Today, UNL provides veterinary education for Nebraska students through a cooperative agreement with Iowa State University College of Veterinary Medicine, and GPVEC still provides fourth-year students critical education and experience in large-animal medicine. Nationally, Great Plains Veterinary Educational Center is recognized for providing outstanding educational opportunities, and veterinary students from across the nation come to Clay Center to gain beef cattle and field experience.

"In the future we will continue to work to strengthen and augment our educational offerings, and initiate new continuing education options," said Grotelueschen. Grotelueschen is just the second director in the 25 year history of the center. Rupp held the position from 1988-2010.

View 2015 Fall Seminar Schedule