期刊
NEW PHYTOLOGIST
卷 230, 期 1, 页码 155-170出版社
WILEY
DOI: 10.1111/nph.17162
关键词
algae; Ca2+ signalling; diatoms; environmental sensing; osmotic stress; Phaeodactylum; R-GECO1; signalling
资金
- European Research Council [ERC-ADG-670390]
- NERC Independent Research Fellowship [NE/R015449/2]
- BBSRC [BB/S019758/1] Funding Source: UKRI
- NERC [NE/R015449/1, NE/R015449/2] Funding Source: UKRI
Diatoms are globally important phytoplankton that dominate coastal and polar-ice assemblages. They employ Ca2+ signaling to respond to osmotic stress and regulate cell volume.
Diatoms are globally important phytoplankton that dominate coastal and polar-ice assemblages. These environments exhibit substantial changes in salinity over dynamic spatiotemporal regimes. Rapid sensory systems are vital to mitigate the harmful consequences of osmotic stress. Population-based analyses have suggested that Ca2+ signalling is involved in diatom osmotic sensing. However, mechanistic insight of the role of osmotic Ca2+ signalling is limited. Here, we show that Phaeodactylum Ca2+ elevations are essential for surviving hypo-osmotic shock. Moreover, employing novel single-cell imaging techniques we have characterised real-time Ca2+ signalling responses in single diatom cells to environmental osmotic perturbations. We observe that intracellular spatiotemporal patterns of osmotic-induced Ca2+ elevations encode vital information regarding the nature of the osmotic stimulus. Localised Ca2+ signals evoked by mild or gradual hypo-osmotic shocks are propagated globally from the apical cell tips, enabling fine-tuned cell volume regulation across the whole cell. Finally, we demonstrate that diatoms adopt Ca2+-independent and dependent mechanisms for osmoregulation. We find that efflux of organic osmolytes occurs in a Ca2+-independent manner, but this response is insufficient to mitigate cell damage during hypo-osmotic shock. By comparison, Ca2+-dependent signalling is necessary to prevent cell bursting via precise coordination of K+ transport, and therefore is likely to underpin survival in dynamic osmotic environments.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据