Transcription profiling of Drosophila second CA/AA time series of y w

ABSTRACT: Circadian clocks are temporally aligned to the environment via signals, or Zeitgebers, such as daily light and temperature cycles, food availability, and social behavior. In this study, we show that genome-wide expression profiles from temperature-entrained flies show a dramatic difference in the presence or absence of a thermocycle. Whereas transcription appears to be modified globally by changes in temperature, there is a specific set of transcripts that continue to oscillate in constant conditions following temperature entrainment. These transcripts show a significant overlap with a previously defined set of transcripts oscillating in response to a photocycle. Further, these overlapping transcripts maintain the same mutual phase relationships after entrainment by temperature or light. Comparison of the collective temperature- and light-entrained circadian phases indicates that natural environmental light and temperature cycles cooperatively entrain the circadian clock. These findings suggest that a single transcriptional clock in the adult fly head is able to integrate information from both light and temperature. Experiment Overall Design: y w flies that had been reared in constant darkness initially at 25 C and later in a 12-hr 18 C/ 12-hr 25 C thermocycle for more than 4 days were harvested every four hours during an additional 18 C/25 C thermo cycle (also indicated as a cold/ambient or CA cycle) or an additional day at constant 25 C (also indicated as ambient/ambient or AA) . Relative to time CA0 as the time of the onset of the 18 C cryophase or AA0 as the time of the onset of the subjective cryophase during constant 25 C, samples were collected in a CA2- Experiment Overall Design: CA6-CA10-CA14-CA18-CA22 and AA2-AA6-AA10-AA14-AA18-AA22 schedule. Heads Experiment Overall Design: were isolated by breaking up frozen flies and passing them through a set of Experiment Overall Design: sieves. RNA was prepared using guanidine-thiocyanate extraction followed by Experiment Overall Design: purification over a CsCl gradient. Additional purification of the RNA samples was Experiment Overall Design: achieved by applying them to Rneasy columns (Qiagen). Biotin-labeled cRNA Experiment Overall Design: probe was generated from 25 μg of purified RNA and hybridized as described Experiment Overall Design: previously (Wijnen H, Naef F, and Young MW, Methods Enzymol. 2005; 393: 341-365). Experiment Overall Design: For more information see also http://biorhythm.rockefeller.edu

ORGANISM(S): Drosophila melanogaster

SUBMITTER: Herman Wijnen 

PROVIDER: E-GEOD-6491 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress