[1] He made his most notable contribution to the field while working with Drosophila in the lab of Seymour Benzer at the California Institute of Technology.
After his stay at Caltech, Konopka accepted a position at Clarkson University but was again denied tenure and subsequently exited the field of science.
Konopka's discovery and genetic analysis of period and several other circadian rhythm mutations became the basis of the research done by Drs.
[5] He used ethyl methanesulfonate (EMS) to induce point mutations in the Drosophila melanogaster genome, and eventually isolated three mutants with abnormal rhythms in eclosion.
The model predicts that the per gene product is active during the subjective day and functions like a pump to establish the gradient.
In two aperiodic strains of D. pseudoobscura, the percentages of abnormally located cells are likewise significantly increased over those in the wild type.
During the collaboration, Konopka worked to understand behaviors of Drosophila per mutants beyond their abnormal period lengths.
[11] Konopka hypothesized that these reciprocal behaviors were a manifestation of two coupled oscillators, a model proposed in 1976 by Pittendrigh and Daan.
[12] In 1990, Konopka collaborated with Mitchell S. Dushay and Jeffery C. Hall to further investigate the effects of the clock gene in D. melanogaster.
[13] By working with Randall F. Smith and Dominic Orr of Caltech, Konopka discovered a new circadian mutant, named Andante, in 1990.