Phototaxis and chemotaxis of brown algal swarmers
Brown algae exhibit three patterns of sexual reproduction: isogamy, anisogamy, and oogamy. Unicellular swarmers including gametes and zoospores bear two heterogenous flagella, an anterior flagellum with mastigonemes (fine tripartite hairs) and a posterior one. In seawater, these flagellates usually receive physico-chemical signals for finding partners and good habitats. It is well known that brown algal swarmers change their swimming direction depending on blue light (phototaxis), and male gametes do so, based on the sex pheromones from female gametes (chemotaxis). In recent years, the comparative analysis of chemotaxis in isogamy, anisogamy, and oogamy has been conducted. In this paper, we focused on the phototaxis and chemotaxis of brown algal gametes comparing the current knowledge with our recent studies.
KeywordsBrown algae Calcium Chemotaxis Flagella Gametes Phototaxis
We sincerely thank Dr. Makoto Terauchi, Kobe University, and Dr. Tatsuya Togashi, Chiba University, for helpful discussions. We also thank Drs. Kogiku Shiba and Kazuo Inaba of the Shimoda Marine Research Center, University of Tsukuba, for their many valuable comments. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
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