Omuro Yoshiki, Khoa Ho Viet, Mikami Koji
Department of Aquaculture Life Science, School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate 041-8611, Japan.
Division of Marine Life Science, Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate 041-8611, Japan.
Plants (Basel). 2021 Mar 1;10(3):465. doi: 10.3390/plants10030465.
The ebb tide causes calm stress to intertidal seaweeds in tide pools; however, little is known about their physiological responses to loss of water movement. This study investigated the effects of static culture of '' sp. ESS1 at 15 °C on tolerance to temperature fluctuation. The freezing of aer-obically cultured thalli at -80 °C for 10 min resulted in the death of most cells. By contrast, statically cultured thalli acquired freezing tolerance that increased cell viability after freeze-thaw cycles, although they did not achieve thermotolerance that would enable survival at the lethal temperature of 32 °C. Consistently, the unsaturation of membrane fatty acids occurred in static culture. Notably, static culture of thalli enhanced the release of asexual spores after freeze-and-thaw treatment. We conclude that calm stress triggers both the acquisition of freezing tolerance and the promotion of freezing-dependent asexual reproduction. These findings provide novel insights into stress toler-ance and the regulation of asexual reproduction in Bangiales.
落潮会给潮间带潮池中潮间带海藻带来平静压力；然而，对于它们对水流丧失的生理反应却知之甚少。本研究调查了在15℃下对ESS1藻株进行静置培养对其温度波动耐受性的影响。将需氧培养的藻体在-80℃下冷冻10分钟导致大多数细胞死亡。相比之下，静置培养的藻体获得了冷冻耐受性，在冻融循环后细胞活力增加，尽管它们没有获得能使其在32℃致死温度下存活的耐热性。同样，膜脂肪酸的不饱和度在静置培养中出现。值得注意的是，藻体的静置培养增强了冻融处理后无性孢子的释放。我们得出结论，平静压力既触发了冷冻耐受性的获得，也促进了依赖冷冻的无性繁殖。这些发现为红毛菜纲的胁迫耐受性和无性繁殖调控提供了新的见解。
