Sexual reproduction of the snow alga Chloromonas fukushimae (Volvocales, Chlorophyceae) induced using cultured materials

• Published in: PloS one Vol. 15; no. 8; p. e0238265
• Main Authors: Matsuzaki, Ryo, Kawachi, Masanobu, Nozaki, Hisayoshi, Nohara, Seiichi, Suzuki, Iwane
• Format: Journal Article
• Language: English
• Published: San Francisco Public Library of Science 26.08.2020; Public Library of Science (PLoS)
• Subjects: Algae; Aquatic microorganisms; Asexuality; Biology; Biology and Life Sciences; Cell culture; Chlorophyceae; Cysts; Digital cameras; Ecosystem biology; Ecosystems; Environmental science; Environmental studies; Experiments; Gametes; Light; Lipid bodies; Lipids; Medicine and Health Sciences; Microbiological research; Microscopy; Morphology; National parks; Nitrogen; Observations; People and Places; Physiological aspects; Reproduction; Reproduction (biology); Research and Analysis Methods; Sexual reproduction; Snow; Snowmelt; Snowpack; Species; Supervision; Vegetative cells; Volvocales; Zygote; Zygotes; Japan
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0238265

Snow algae are microalgae, growing in melting snowpacks, and are thought to act as primary producers in the snow ecosystem. Chloromonas (Volvocales, Chlorophyceae) contains more than 15 snow-inhabiting species. Although vegetative cells and zygotes, or asexual cysts, of snow species of the genus are frequently collected in the field, sexual reproduction and zygote formation in culture have only been induced in C. tughillensis. Here we describe the sexual reproduction of another snow-inhabiting species, C. fukushimae, which was induced using both previously examined and newly established Japanese strains. Mating of isogamous gametes began after mixing two different strains, implying that C. fukushimae is an outcrossing species. Motile and nonmotile zygotes of the species were also described in this report. The nonmotile zygote of C. fukushimae was distinguishable from those of the other snow-inhabiting species of Chloromonas, based on the zygote shape and the presence of several large lipid bodies within the cell. In addition, C. fukushimae carried out sexual reproduction and produced zygotes even under the nitrogen-sufficient condition.