Algae. 2011; 26(1): 87-96.
Comparative proteomics of the mixotrophic dinoflagellate Prorocentrum micans growing in different trophic modes
Junbo Shim1, Tatyana A. Klochkova1, Jong Won Han1, Gwang Hoon Kim1,*, Yeong Du Yoo2 and Hae Jin Jeong2
1Department of Biology, Kongju National University, Kongju 314-701, Korea
2School of Earth and Environmental Sciences, College of Natural Sciences, Seoul National University, Seoul 151-747, Korea
Protein profiles of a common mixotrophic dinoflagellate, Prorocentrum micans, growing autotrophically and mixotrophically (fed on the cryptophyte Rhodomonas salina) were compared using two-dimensional gel electrophoresis (2-DE) to determine if they vary in different trophic modes. Approximately 2.3% of the detected proteins were differentially expressed in the different trophic modes. Twelve proteins observed only in the mixotrophic condition had lower pI value (5). When the internal amino acid sequences of five selected proteins differentially expressed between autotrophic and mixotrophic conditions were analyzed using matrix-assisted laser desorption time-of-flight (MALDI-TOF) mass spectrometry, two proteins that were specifically expressed in the autotrophic condition showed homology to glyceraldehyde-3-phosphatase dehydrogenase (GAPDH) and a bacterial catalase. Three mixotrophy-specific proteins showed homology to certain hypothetical proteins from an insect and bacteria. These results suggested the presence of certain gene groups that are switched on and off according to the trophic mode of P. micans.
cryptophyte; feeding; mixotrophy; Prorocentrum micans; proteomic; Rhodomonas salina