The overall goal of this project is to gain insight into the mechanisms that generate the rhythms of life. The circadian clock is an endogenous timing system that exists in all kingdoms of life, from bacteria to animals. Its main function is to enable the integration of environmental signals and metabolic status to ensure that organisms perform necessary tasks at biologically advantageous times of day. It is known that protein-protein interactions are important in the transduction of circadian timing information within an organism. Although a number of key conserved proteins that make up the core oscillator in the circadian timing system have been identified in animals, the mechanisms by which the oscillator protein module receives input time cues and subsequently transduces this timing information to generate physiological rhythms are not well understood. In this project, protein network analysis centering on the oscillator protein module in three insect species with distinct clock designs will be conducted using mass spectrometry-based analyses over a circadian timeframe. Algorithms will be developed to model the dynamic changes in the network connections between the oscillator and cellular protein complexes with respect to circadian as well as evolutionary time. This project will uncover previously unknown protein interactions and shed light on the dynamic protein network rewiring necessary for properly timed biological activities. This project will provide training opportunities and career development for graduate students, undergraduates, high school teachers and students from K-12 levels. Exhibits showcasing insect circadian rhythms will be organized at the Bohart Museum of Entomology at UC Davis. Laboratory workshops providing hands on laboratory experience will be organized to benefit high school teachers and students. Video training tools will be developed as resources for laboratory workshops and for training students involved in this project.
This project aims to profile and model temporally-regulated and dynamic protein networks centered on core transcription factors that make up the circadian oscillators in three insect species, Drosophila melanogaster, the Monarch butterfly Danaus plexippus, and the honeybee Apis mellifera. Interactomic comparisons between these relatively closely related insect species with distinct clock designs will be valuable not only in identifying conserved and likely important cellular protein modules for clockworks, but also in highlighting network rewiring and differential interactions that can reflect inherent flexibility and adaptability of the clock network. Results from this project will lay the foundation for testing new hypotheses regarding animal clockwork and predicting the behavior of the clock system in response to perturbations. Since protein networks are tissue and cell-type specific, a novel framework to overcome current limits of mass spectroscopy sensitivity and model cell-type specific protein networks from network data assembled from broader tissue samples using a trans-omics approach will be tested. This project will develop proteomic methods as well as bioinformatic tools for understanding a dynamic and oscillating biological system, all of which will be valuable to the scientific community.
