Systems Biology Commons^™

Planarian Cholinesterase: Molecular And Functional Characterization Of An Evolutionarily Ancient Enzyme To Study Organophosphorus Pesticide Toxicity, D. Hagstrom, S. Zhang, A. Ho, E. S. Tsai, Z. Radić, A. Jahromi, K. J. Kaj, Y. He, P. Taylor, Eva-Maria S. Collins

Biology Faculty Works

The asexual freshwater planarian Dugesia japonica has emerged as a medium-throughput alternative animal model for neurotoxicology. We have previously shown that D. japonica are sensitive to organophosphorus pesticides (OPs) and characterized the in vitro inhibition profile of planarian cholinesterase (DjChE) activity using irreversible and reversible inhibitors. We found that DjChE has intermediate features of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Here, we identify two candidate genes (Djche1 and Djche2) responsible for DjChE activity. Sequence alignment and structural homology modeling with representative vertebrate AChE and BChE sequences confirmed our structural predictions, and show that both DjChE enzymes have intermediate sized catalytic gorges …