- BMB, Michael Rust Laboratory
The University of Chicago-IGSB
900 E. 57th, St. KCBD 10th Floor
Chicago, IL 60637
I am interested in the biochemical mechanism of the KaiABC circadian clock from the cyanobacterium S. elongatus. The three proteins KaiA, KaiC, and KaiC form a circadian oscillator independent of transcriptional/translational feedback mechanisms. The KaiABC clock can be reconstituted in vitro to generate sustained oscillations in the phosphorylation of KaiC with a 24 hour period. In the oscillator, KaiA binds KaiC to activate its kinase activity, leading to its autophosphorylation and KaiB negatively feedbacks on KaiC phosphorylation to inhibit KaiA activity. While it is known that this negative feedback involves the selective binding of KaiB to phosphorylated KaiC, how this leads to KaiA inhibition and KaiC dephosphorylation is still unclear. This is the current focus of my research; I am combining both experimental and computational approaches to define a clearer mechanistic model of the KaiABC oscillator.