Lee Bulla Jr

Professor - Biological Sciences
bulla@utdallas.edu
972-883-4226
FN3112
UTD Webpage

Professional Preparation

Postdoctoral Research Associate
Northern Regional Research Laboratory, USDA, Peoria, IL - 1969
Ph.D. - Microbiology
Oregon State University - 1968
B.S. - Biology
Midwestern State University - 1965

Research Areas

Research Interests
Many subspecies of the soil bacterium Bacillus thuringiensis produce various parasporal crystal proteins, also known as Cry toxins, that exhibit insecticidal activity upon binding to specific receptors in the midgut of susceptible insects. One such receptor, BT-R1(210 kDa), is a cadherin located in the midgut epithelium of the tobacco hornworm, Manduca sexta. It has a high binding affinity (Kd~1 nM) for the Cry1A toxins of B. thuringiensis. Truncation analysis of BT-R1 revealed that the only fragment capable of binding the Cry1A toxins of B. thuringiensis is a contiguous 169-amino acid sequence adjacent to the membrane-proximal extracellular domain. The purified toxin-binding fragment acts as an antagonist to Cry1Ab toxin by blocking the binding of toxin to the tobacco hornworm midgut and inhibiting insecticidal action. Exogenous Cry1Ab toxin bound to intact COS-7 cells expressing BT-R1 cDNA, subsequently killing the cells. Recruitment of BT-R1 by B. thuringiensis indicates that the bacterium interacts with a specific cell adhesion molecule during its pathogenesis. Apparently, Cry toxins, like other bacterial toxins, attack epithelial barriers by targeting cell adhesion molecules within susceptible insect hosts.

Publications

Griko, N., M. Candas, X. Zhang, M. Junker and L. A. Bulla, Jr. 2004. Selective antagonism of the cadherin BT-R1 interferes with calcium-induced adhesion of epithelial membrane vesicles. Biochemistry. In press. 2004 - Publication
Midboe, E. G., M. Candas and L. A. Bulla, Jr. 2003. Expression of a midgut-specific cadherin BT-R1 during the development of Manduca sexta. Comp. Biochem. Physiol., Part B 135: 125-137. 2003 - Publication
Candas, M., O. Loseva, B. Oppert, P. Kosaraju and L. A. Bulla, Jr. 2003. Insect resistance to Bacillus thuringiensis: alterations in the Indianmeal moth larval gut proteome. Mol. Cell Proteomics. 2: 19-28. 2003 - Publication
Candas, M., Francis, B. R. Griko, N. B. Midboe, E. G. and Bulla, L. A. Jr. 2002. Proteolytic cleavage of the developmentally important cadherin BT-R1 in the midgut epithelium of Manduca sexta. Biochemistry 41: 13717-13724. 2002 - Publication
Loseva, O., M. Ibrahim, M. Candas, C. N. Koller, L. S. Bauer and L. A. Bulla, Jr. 2002. Changes in protease activity and Cry3Aa toxin binding in the Colorado potato beetle: implications for insect resistane to Bacillus thuringiensis toxins. Insect Biochem. Mol. Biol. 32: 567-77. 2002 - Publication

Appointments

Director - University of Texas at Dallas [1999–Present]
Professor - University of Texas at Dallas [1998–Present]
Chairman - University of Wyoming [1991–1995]
Director - University of Wyoming [1991–1995]
Professor - University of Wyoming [1984–1998]
Dean - University of Wyoming [1984–1990]
Director - University of Idaho [1982–1984]
Associate Dean for Research - University of Idaho [1981–1984]
Professor - University of Idaho [1981–1984]
Director - University of Idaho [1981–1984]

Activities

Synergistic Activities
  1. American Academy of Microbiology, Special Project on "100 Years of Bacillus thuringiensis-- A Paradigm for Transgenic Organisms: A Critical Scientific Assessment." 2001.
  2. Institutional Biosafety Committee, Universiity of Texas at Dallas, 1999-2002.
  3. Texas Healthcare & Bioscience Institute, 1998-present.
  4. Joint Graduate Studies Committee in Biomedical Engineering, University of Texas Southwestern Medical Center, 2000-present.
  5. Dean's Council, School of Natural Sciences and Mathematics, University of Texas at Dallas, 1999-present.
  6. Intellectual Property Committee, University of Texas at Dallas, 1999-present.
  7. Health Profession Advisory Committee, School of Natural Sciences & Mathematics, University of Texas at Dallas, 1999-present.

Affiliations

Thesis Advisor and Postgraduate-Scholar Sponsor
Ph.D. Students Postdoctoral Associates Xuebin Zhang - current Natalya Griko - current Pradeepa Kosaraju - current Olga Loseva - 2000-2002 Veniamin Slavitskiy - current Jason Meng - 1996-1998 Eric Midboe - 1999 Timothy Keeton - 1996-1998 Walid Maaty - 1999 Scott Franklin - 1996-1998 Mohamed Ibrahim - 1999 Brian Francis - 1995-1998 John Dorsch - 1998 Yehia Osman - 1995-1998
Other Affiliations
2001-present Adjunct Professor, Department of Chemistry, University of Texas at Dallas, Richardson, TX 2001- present Adjunct Professor, Joint Program in Biomedical Engineering, University of Texas Southwestern Medical Center, Dallas, TX
Collaborators
Antich, Peter The University of Texas Southwestern Health Science Center at Dallas Bonte, Frederick The University of Texas Southwestern Health Science Center at Dallas Dyer, David University of Oklahoma Health Sciences Center Federici, Brian University of California at Riverside Gillaspy, Allison University of Oklahoma Health Sciences Center Johnson, Arthur Texas A&M University Koehler, Theresa The University of Texas Health Science Center at Houston Machius, Mischa The University of Texas Southwestern Health Science Center at Dallas Ravel, Jacque The Institute for Genomic Research (TIGR) White, Charles The University of Texas Southwestern Health Science Center at Dallas Wirth, Margaret University of California at Riverside
Graduate and Postdoctoral Advisors
Thesis advisor: W. B. Bollen, Oregon State University Postdoctoral advisor: R. A. Rhodes, Northern Regional Research Center, USDA, Peoria, IL