Applying -omics methods to map the circadian matrisome

Circadian rhythm regulates and synchronises biological processes through a daily cycle. Molecular clocks in cells throughout the human body are entrained to a 'master clock' located in the hypothalamus, and cells in almost all tissues have been found to contain rhythmic genes. Circadian rhythm ensures the correct sequence and regulation of a broad range of cellular and organ functions. Consequently, disruption to the cycle - for example, in shift-workers - has been linked to risk in many diseases, including hypertension, inflammatory, metabolic and neurological disorders.

Recent work, for example in mouse liver, has shown circadian rhythm in transcriptional regulation to be propagated through to protein levels and post-translational modifications of proteins. Remarkably, a study by the project management team has demonstrated that the secretory system for extracellular matrix proteins - the proteins that provide persistent, life-long structure to the body - also falls under circadian regulation in tendon tissue. The purpose of this project is to discover the extent to which circadian oscillations occur in extracellular matrix proteins throughout the body (the 'matrisome'), and how these and other rhythmic processes can contribute to the healthy maintenance of tissues subjected to daily activity.

An initial task will be to mine existing transcriptional datasets to identify characteristic circadian regulation of secretory-pathway and matrix proteins, informed by our earlier work on tendon, cartilage and intervertebral disc. Candidate tissues, such as skin, will be isolated from mice at defined time-points and subjected to proteomic analysis. There will be opportunity here to learn and develop methods for sample preparation, data processing and interpretation. Unbiased -omics approaches will inform on multiple pathways, including secretion, autophagy, stress response and regulation of cell structure. This will enable us to build an integrated, holistic picture of the fundamental intracellular signalling and secretion pathways that maintain extracellular matrix homeostasis. The importance of key pathways will be tested through manipulation of cell and mouse model systems. Finally, we would like the project to establish an internet-based database of the "circadian matrisome", thus providing benefit to the broader matrix and chronobiology communities.

This is a 'Underpinning Biosciences' project that will encompass aspects of chronobiology, cell biology, matrix biology, bioinformatics and biophysics. The multidisciplinary nature of the work, and its close integration of quantitative and -omics methodologies, make it an ideal fit to the BBSRC's ENWW remit. The work will be performed in partnership with SCIEX (Cheshire, UK) - a leading developer of instruments for mass spectrometry. This collaboration will give access to training, technical expertise and the latest proteomics technology.