- The sluggish-A gene of Drosophila melanogaster is expressed in the nervous system and encodes proline oxidase, a mitochondrial enzyme involved in glutamate biosynthesis. Hayward, D.C., Delaney, S.J., Campbell, H.D., Ghysen, A., Benzer, S., Kasprzak, A.B., Cotsell, J.N., Young, I.G., Miklos, G.L. Proc. Natl. Acad. Sci. U.S.A. (1993)









