Komoike Yuta
   Department   School of Medicine, School of Medicine
   Position   Associate Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Cellular responses of the ciliate, Tetrahymena thermophila, to far infrared irradiation.
Journal Formal name:Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology
Abbreviation:Photochem Photobiol Sci
ISSN code:1474-905X
Volume, Issue, Page 5(9),pp.799-807
Author and coauthor Shiurba Robert, Hirabayashi Tatsuo, Masuda Masaru, Kawamura Akinori, Komoike Yuta, Klitz William, Kinowaki Keiichi, Funatsu Takashi, Kondo Shunzo, Kiyokawa Shin, Sugai Toshiro, Kawamura Kosuke, Namiki Hideo, Higashinakagawa Toru
Publication date 2006/09
Summary Infrared rays from sunlight permeate the earth's atmosphere, yet little is known about their interactions with living organisms. To learn whether they affect cell structure and function, we tested the ciliated protozoan, Tetrahymena thermophila. These unicellular eukaryotes aggregate in swarms near the surface of freshwater habitats, where direct and diffuse solar radiation impinge upon the water-air interface. We report that populations irradiated in laboratory cultures grew and mated normally, but major changes occurred in cell physiology during the stationary phase. Early on, there were significant reductions in chromatin body size and the antibody reactivity of methyl groups on lysine residues 4 and 9 in histone H3. Later, when cells began to starve, messenger RNAs for key proteins related to chromatin structure, intermediary metabolism and cellular motility increased from two- to nearly nine-fold. Metabolic activity, swimming speed and linearity of motion also increased, and spindle shaped cells with a caudal cilium appeared. Our findings suggest that infrared radiation enhances differentiation towards a dispersal cell-like phenotype in saturated populations of Tetrahymena thermophila.
DOI 10.1039/b601741j
PMID 17047831