Biological rhythmicity in expressed proteins of the marine dinoflagellate Lingulodinium polyedrum demonstrated by chronological proteomics.

The dinoflagellate Lingulodinium polyedrum shows circadian expression of proteins. Analysis of the expression profile of ca. 900 proteins (pI range 5-8; MW 22,000-120,000) by chronological proteomics in 12:12h light-dark ('day-night') cycles revealed 28 with quantitative circadian changes. The patterns were classified into three types: Phase 1 ('evening'), Phase 2 ('night'), and Phase 3 ('midnight'). Peptide mass fingerprinting identified luciferin-binding protein in Phase 2 and two components of the tricarboxylic acid cycle in Phases 1 and 2. Thus, rhythmicity appears to be related to physiological states and to control the metabolic pathway in L. polyedrum.