Chronobiological rhythms control of site- and cell-specific miRNA and mRNA genes and networks across the central nervous system

Abstract

Biological rhythms control gene expression, but effects on central nervous system (CNS) cells and structures remain undefined. While circadian (24-hour) rhythms are most studied, many genes have periods of greater and less than 24-hours; these fluctuations can be both site- and cell-specific. Identifying patterns of gene rhythmicity across the CNS is necessary for both the study of chronobiology and to make sense of data obtained in the laboratory. We now identify cycling mRNAs, miRNAs, gene networks and novel mRNA-miRNA co-expression pairs in the cortex, hypothalamus, and corpus striatum using high-dimensional datasets. A searchable catalogue (https://www.ghasemloulab.ca/chronoCNS) was created to help refine the analysis of cellular/molecular rhythmicity across the CNS. Immunofluorescence was also used to confirm the rhythmicity of key targets across cells in these structures, with strong cycling signatures in resting oligodendrocytes. Our study sheds light on the contribution of circadian, ultradian, and infradian rhythms and mRNA-miRNA interactions to CNS function.