Molecular basis of circadian rhythmicity in renal physiology and pathophysiology.

What is the topic of this review? This brief symposium report is focused on the molecular and physiological evidence that supports a key role for the circadian clock in the regulation of kidney function. What advances does it highlight? Progress in understanding the molecular mechanism of the kidney clock is reviewed here, including new results from global 'omics' studies and candidate gene approaches. The molecular kidney clock is a master regulator of gene expression that affects renal electrolyte and drug handling as well as blood pressure. In this brief review, an overview of the molecular and physiological evidence for the kidney clock and the implications for the regulation of renal physiology and pathophysiology are presented. Accumulating evidence suggests that the molecular circadian clock acts as a master regulator of gene expression in the kidney. Global transcriptomic approaches have revealed the important finding that there are thousands of genes in the kidney subject to regulation by the molecular clock. Candidate gene approaches have also yielded information regarding regulation of renal sodium transport genes by the molecular clock. To date, the evidence linking the molecular kidney clock to rhythmic renal function provides strong support for the concept that circadian control of gene expression underlies rhythms in physiological function.