Correlated evolution between CK1? Protein and the Serine-rich Motif Contributes to Regulating the Mammalian Circadian Clock.

ABSTRACT: Understanding the mechanism underlying the physiological divergence of species is a long-standing issue in evolutionary biology. The circadian clock is a highly conserved system existing in almost all organisms that regulates a wide range of physiological and behavioral events to adapt to the day-night cycle. Here, the interactions between hCK1?/?/DBT (Drosophila ortholog of CK1?/?) and serine-rich (SR) motifs from hPER2 (ortholog of Drosophila per) were reconstructed in a Drosophila circadian system. The results indicated that in Drosophila, the SR mutant form hPER2S662G does not recapitulate the mouse or human mutant phenotype. However, introducing hCK1? (but not DBT) shortened the circadian period and restored the SR motif function. We found that hCK1? is catalytically more efficient than DBT in phosphorylating the SR motif, which demonstrates that the evolution of CK1? activity is required for SR motif modulation. Moreover, an abundance of phosphorylatable SR motifs and the striking emergence of putative SR motifs in vertebrate proteins were observed, which provides further evidence that the correlated evolution between kinase activity and its substrates set the stage for functional diversity in vertebrates. It is possible that such correlated evolution may serve as a biomarker associated with the adaptive benefits of diverse organisms. These results also provide a concrete example of how functional synthesis can be achieved through introducing evolutionary partners in vivo.

SUBMITTER: Xing L 

PROVIDER: S-EPMC5217676 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature