Ping Wang
My research concerns the biochemical and molecular basis of insect midgut physiology and interactions of the midgut with host plants and microbial pathogens.
Research Foci
Molecular basis of physiological and defense mechanisms in the insect midgut
The insect midgut plays the most essential physiological function - food digestion and nutrient intake - and is the primary site interfacing with chemical, physical and biological factors from the environment. Our research is focused on the biochemical and molecular basis of important physiological and defense mechanisms in the midgut of the cabbage looper, Trichoplusia ni. One goal of this research is to identify new insect target sites/mechanisms to facilitate development of novel strategies for insect control.
Molecular Structure and Function of the Insect Midgut Peritrophic Membrane
The gut lining in animals is a primary site interfacing with the environment and serves as the first line of defense. In insects, the gut epithelium is lined by the peritrophic membrane (or peritrophic matrix) (PM), a unique protein-chitin structure functionally analogous to the human intestinal mucus. Our research on the PM has led to the discoveries of the first insect intestinal mucin (IIM), the first member of a new family of chitin deacetylase-like proteins from insects, and a novel mechanism that an animal virus (an insect pathogenic baculovirus) has evolved to overcome a mucinous protective barrier in host animals. We are using physiological, biochemical, proteomic and molecular approaches to study the roles of PM proteins in the PM formation and function.
Mechanisms of Insect Resistance to Bacillus thuringiensis (Bt) Toxins
Bt is the most successfully utilized biological agent for insect control. Recently, transgenic crops expressing Bt toxins have been widely and increasingly planted for insect pest control. The widespread Bt applications and large-scale planting of Bt crops have created the risk of evolution of Bt resistance in insect populations, which threatens environmentally sustainable pest management programs. Our research aims to understand the molecular mechanisms of Bt resistance evolved in insect populations in agricultural production systems. Our research on Bt resistance in commercial greenhouse populations of T. ni has indicated that the Bt resistance evolved in the agricultural system is conferred by a novel but unknown mechanism. Our research aims to identify the molecular mechanisms for the field-evolved Bt resistance in insects and contribute knowledge necessary for sustainable application of Bt for insect control.
Molecular Diagnostics of Insect Pests
We are interested in developing and applying molecular techniques in insect pest management (IPM) programs. Our projects include development and application of molecular diagnostic techniques for identification of invasive insect pests, and identification and use of molecular markers to study population structure, development and movement of insect pests.
Selection of Recent Publications
Wang, P., Zhao, J.-Z., Rodrigo-Simon, A., Kain, W., Janmaat, A. F., Shelton, A. M., Ferre, J. and Myers, J. (2007) Mechanism of resistance to Bacillus thuringiensis toxin Cry1Ac in a greenhouse population of cabbage looper, Trichoplusia ni. Applied and Environmental Microbiology 73: 1199-1207. Pubmed
Guo, W., Li, G., Pang, Y. and Wang, P. (2005) A novel chitin-binding protein identified from the peritrophic membrane of the cabbage looper, Trichoplusia ni. Insect Biochemistry and Molecular Biology 35: 1224-1234. Pubmed
Wang, P., Zhang, X. and Zhang, J. (2005) Molecular characterization of four midgut aminopeptidase N isozymes from the cabbage looper, Trichoplusia ni. Insect Biochemistry and Molecular Biology 35: 611-620. Pubmed
Wang P, Li G and Granados RR. 2004. Identification of two new peritrophic membrane proteins from larval Trichoplusia ni: structural characteristics and their functions in the protease rich insect gut. Insect Biochemistry and Molecular Biology 34: 215-227. Pubmed
Wang, P., Li, G. and Kain, W. (2004) Characterization and cDNA cloning of midgut carboxypeptidases from Trichoplusia ni. Insect Biochemistry and Molecular Biology 34: 831-843. Pubmed
Larval midgut proteases from different individuals of two strains of Trichoplusia ni studied by protease zymography to examine the potential involvement of midgut proteases in resistance to Bt-toxins. [Wang et al. 2007. Applied and Environmental Microbiology 73, 1199-1207] 