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James E. Schoelz was born in Arcadia, California. He graduated from Point Loma Nazarene University in San Diego, California with a B.A. in Biology-Chemistry in 1980. He received a Ph.D. in Plant Pathology from the University of Kentucky (1986) under the direction of Robert J. Shepherd, followed by one year of postdoctoral research in the Department of Plant Pathology at Cornell University under the direction of Milton Zaitlin. Schoelz joined the Department of Plant Pathology at the University of Missouri-Columbia in 1987 as an Assistant Professor. He is currently Professor and Director of Graduate Studies in the Division of Plant Sciences.
During his research career, Schoelz has consistently made important discoveries that have significantly advanced our understanding of plant-virus interactions, with a particular emphasis on caulimoviruses. He was the first to use recombinant DNA techniques to identify a viral avirulence gene, developing the strategy of gene exchanges between infectious clones of Cauliflower mosaic virus (CaMV) strains to make the fascinating discovery that its P6 gene was both an avirulence gene (triggering a hypersensitive response in Datura and Nicotiana species) and a virulence gene (responsible for development of the mosaic symptom in susceptible hosts). Schoelz later extended these findings, revealing that the P6 gene also triggered a form of non-necrotic plant defense in other Nicotiana species.
This led to a lifelong interest in the relationship of cell death and plant defenses, as exemplified by showing that cell death could be genetically uncoupled from resistance in the hypersensitive response (HR)—one of the first such reported findings in plant pathology. For this, he showed that a systemic cell death symptom in N. clevelandii was the consequence of a gene-for-gene interaction between a single host gene product and the CaMV P6 protein. Schoelz subsequently demonstrated he could reconstitute an HR in an interspecific F1 hybrid between N. glutinosa (non-necrotic resistance response) and N. clevelandii (systemic necrosis response). Furthermore, all four categories of plant responses, with respect to cell death and plant defenses, were recovered in the F2 progeny: HR, non-necrotic resistance, systemic mosaic, and systemic cell death.
Again, working on host-virus interactions, Schoelz wondered if there were viruses that elicited non-necrotic resistance. These studies led to the serendipitous discovery that CaMV transgene-expressing plants inoculated with infectious caulimoviruses were capable of recombining with and acquiring the transgene through a gene conversion mechanism. Later studies defined the parameters that contributed to recombination between the CaMV isolate and the CaMV transgene. For example, Schoelz recognized early on that the acquisition of virus transgenes by viruses would likely be limited to close relatives. At the time, the initial findings were very controversial, because the technology for virus-resistant transgenic plants was being commercialized. This work soon was confirmed by others who replicated it for various plant viruses; it is now accepted that under certain conditions plant viruses can acquire virus transgenes.
Schoelz has also developed new, innovative strategies to use the genus Nicotiana as a genetic resource for virus resistance genes. In the 20th century, virologists characterized plant viruses through host range tests, providing a wealth of information regarding the response of Nicotiana species to virus infection. The genus Nicotiana also has been the subject of numerous phylogenetic studies, which provided Schoelz and colleagues with an opportunity to limn the evolution of R-genes in the genus, by comparing the presence of resistance genes with the phylogenetic relationships of Nicotiana species. He has identified at least three types of R-genes that have evolved within separate clades of the genus to recognize the tombusvirus P19, P22 and coat proteins. As noted by Schoelz, these very intriguing findings form the basis for a comprehensive survey for inheritance of virus R-genes in the genus Nicotiana.
Throughout his career, Schoelz has continued to be fascinated with the role of the CaMV P6 protein effector in the viral disease cycle. Schoelz recently uncovered a new role for the P6 effector protein in intracellular movement. CaMV P6 protein is the primary matrix for the amorphous inclusion bodies. Schoelz suggests that P6 inclusion bodies should be considered complex pathogen organelles that move on microfilaments for delivery of CaMV virions to plasmodesmata, among other functions. He is developing a protein interactome map for the P6 protein effector to illustrate how CaMV P6 can mediate a diverse range of processes in the plant including translation of viral proteins from the CaMV 35S RNA, suppression plant defenses, delivery of virions to plasmodesmata, and elicitation of disease symptoms; this will likely redefine our understanding of the life history of this virus.
In addition, to his impressive research portfolio, Schoelz has remained deeply committed to teaching undergraduate and graduate courses. Currently, he has primary responsibility for Introductory Plant Pathology, Professionalism and Ethics, Graduate Seminar, and Scientific Writing. He also contributes to Research with Plant Stress Agents and Introduction to Plant Stress Biology. Schoelz is an enthusiastic and caring mentor, having trained a dozen doctoral and masters students who have pursued careers in industry, government, academia, and international research institutes.
Schoelz also served as Chair of Plant Microbiology and Pathology at the University of Missouri (2002-2005) and, when the Plant Pathology program was merged with Agronomy and Entomology to form the Division of Plant Sciences, he served as the coordinator for the Plant Pathology Program Area. Since 2009 he has been the Director of Graduate Studies of the Division of Plant Sciences. Schoelz worked closely with a colleague in 2010 to develop a new program in Plant Stress Biology, an effort to integrate studies of biotic and abiotic stresses. For these efforts, in 2013 Schoelz named the University of Missouri Outstanding Director of Graduate Studies.
Schoelz was an Associate (1999-2001) and Senior Editor (2001-2003) for Molecular-Plant Microbe Interactions, Chair of the Plant Virology Committee (2003), and ongoing committee service to APS, as well as organizing several symposia. He also has served as an Associate Editor for the journal Virology for more than 15 years; and as Panel Manager for the USDA-NIFA-AFRI plant molecular interactions grants program (2015).