The testis-specific gene Jingwei (jgw) is a newly evolved short-chain dehydrogenase/reductase in Drosophila. Preliminary substrate screening indicated that JGW prefers long-chain primary alcohols as substrates, including several exotic alcohols such as farnesol and geraniol. Using steady-state kinetics analyses and molecular docking, we not only confirmed JGW's substrate specificity, but also demonstrated that the new enzymatic activities of JGW evolved extensively after exon-shuffling from a preexisting enzyme. Analysis of JGW orthologs in sister species shows that subsequent evolutionary changes following the birth of JGW altered substrate specificities and enzyme stabilities. Our results lend support to a general mechanism for the evolution of a new enzyme, in which catalytic chemistry evolves first followed by diversification of substrate utilization.
Bibliographical noteFunding Information:
We thank all the members in the Dean laboratory at the University of Minnesota, Li laboratory at Northwestern University, and Long laboratory at the University of Chicago for experimental assistance and helpful discussions. This study was supported by grants to A.M.D. from the National Institutes of Health, L.L from National Institute of Health (R01NS056086), and M.L. from the National Science Foundation and the National Institutes of Health, a National Science Foundation CAREER award, and a Packard Fellowship in Science and Engineering. Hinds fund from the University of Chicago to J.Z.
- Drosophila alcohol dehydrogenase
- Enzyme evolution
- Short-chain dehydrogenase/reductase