AUTHOR=Costa Rodolfo TITLE=Frontiers in Chronobiology: Endogenous Clocks at the Core of Signaling Pathways in Physiology JOURNAL=Frontiers in Physiology VOLUME=12 YEAR=2021 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2021.684745 DOI=10.3389/fphys.2021.684745 ISSN=1664-042X