Abstract
Transgenic flies carrying a 7.2 kb piece of DNA from the
period (per) gene were analyzed for the presence of circadian locomotor activity rhythms and fluctuations of
per-encoded mRNA and protein. The 5′ end of this genomic fragment is within the first intron, which precedes the coding region. This promotorless fragment could rescue circadian behavioral rhythms and mediate spatial expression of PER in a subset of wild-type
per cells within the CNS and PNS. In one behaviorally rhythmic line, PER protein was found in only “
per lateral neurons.” In the rhythmic transgenics,
per mRNA and protein levels undergo circadian cycling, as previously described for wild type. Cycling of PER in brain cells of flies carrying the same 7.2 kb piece of
per DNA under the control of a
heat shock promotor corroborated the hypothesis that
per's molecular cyclings and behavioral rhythmicity are causally related.