Project description:Circadian clocks coordinate time-of-day specific metabolic and physiological processes to maximize performance and fitness. In addition to light, which is considered the strongest time cue to entrain animal circadian clocks, metabolic input has emerged as an important signal for clock modulation and entrainment, especially in peripheral clocks. Circadian clock proteins have been to be substrates of O-GlcNAcylation, a nutrient sensitive post-translational modification (PTM), and the interplay between clock protein O-GlcNAcylation and other PTMs, like phosphorylation, is expected to facilitate the regulation of circadian physiology by metabolic signals. Here, we used mass spectrometry proteomics to identify PTMs on PERIOD, the key biochemical timer of the Drosophila clock, over the circadian cycle.
Project description:Circadian clocks have evolved as time-measuring molecular devices to help organisms adapt their physiology to daily changes in light and temperature. Cycling transcription has been long hypothesized to account for the wealth of rhythmic protein abundance. However, cyclic degradation signals such as ubiquitylation could shape the rhythmic protein landscape as well. In order to document the circadian ubiquitylated proteome of Drosophila melanogaster, we took advantage of a new means of Ub purification based on in vivo biotinylation of AviTag-tagged ubiquitin by the BirA protein, the bioUb system. NeutrAvidin-bound fractions of head lysates were collected at four circadian times six hours apart and proteins were identified and quantified using a proteomic-based approach.
