The Drosophila double-timeS Mutation Delays the Nuclear Accumulation of period Protein and Affects the Feedback Regulation of period mRNA

摘要: The Drosophila double-time (dbt) gene, which encodes a protein similar to vertebrate epsilon and delta isoforms of casein kinase I, is essential for circadian rhythmicity because it regulates the phosphorylation stability period (per) protein. Here, phenotype short-period dbt mutant allele (dbt(S)) was examined. dbt(S) locomotor activity rhythm varied little when tested at constant temperatures ranging from 20 29 degrees C. However, per(L);dbt(S) flies exhibited lack temperature compensation like that long-period (per(L)) flies. Light-pulse phase-response curves were obtained wild-type, (per(S)), genotypes. For per(S) genotypes, phase changes larger than those wild-type flies, transition delays advances shorter, light-insensitive shorter. Immunohistochemical analysis per levels demonstrated accumulates in photoreceptor nuclei later declines lower Immunoblot total accumulation heads neither delayed nor reduced, whereas RNase protection mRNA sooner heads. These results suggest can regulate feedback on its by delaying time translocated altering level nuclear PER during declining cycle.