Download MendeleyStructure and Function from the Circadian Clock Protein KaiA of Synechococcus elongatus: A potential Clock Input Mechanism
Williams, S.B., Vakonakis, I., Golden, S.S., LiWang, A.C.(2002) Proc Natl Acad Sci U S A 99: 15357-15362
- PubMed: 12438647
- DOI: https://doi.org/10.1073/pnas.232517099
- Primary Citation of Related Structures:
1M2E, 1M2F - PubMed Abstract:
In the cyanobacterium Synechococcus elongatus (PCC 7942) the proteins KaiA, KaiB, and KaiC are required for circadian clock function. We deduced a circadian clock function for KaiA from a combination of biochemical and structural data. Both KaiA and its isolated carboxyl-terminal domain (KaiA180C) stimulated KaiC autophosphorylation and facilitated attenuation of KaiC autophosphorylation by KaiB. An amino-terminal domain (KaiA135N) had no function in the autophosphorylation assay. NMR structure determination showed that KaiA135N is a pseudo-receiver domain. We propose that this pseudo-receiver is a timing input-device that regulates KaiA stimulation of KaiC autophosphorylation, which in turn is essential for circadian timekeeping.
Organizational Affiliation:
Department of Biology, Texas A&M University, College Station 77843, USA.
