Diatoms exhibit dynamic chloroplast calcium signals in response to high light and oxidative stress
Diatoms exhibit dynamic chloroplast calcium signals in response to high light and oxidative stress
复制标题
硅藻表现出动态叶绿体钙信号以响应强光和氧化应激
DOI：
10.1101/2023.08.15.553405
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Flori S
中科院分区：
文献类型：
--
作者：
Flori S
硅藻是一组硅化藻类，在海洋和淡水生态系统中发挥着重要作用。硅藻叶绿体是通过次生内共生获得的，与陆生植物和绿色藻类的原生质体在结构和功能上有很大差异。初生质体的许多功能，包括光适应和无机碳的获取，都受到钙依赖的信号转导过程的调控。钙信号也被牵连在硅藻的光保护反应;然而，硅藻叶绿体中钙升高的性质及其在细胞信号传导中的更广泛作用仍然未知。利用遗传编码的钙指示剂，我们发现，在叶绿体基质内的三角褐指藻表现出动态钙升高。基质钙（[Ca 2 +]str）独立于胞质溶胶发挥作用，并且不会因诱导大的胞质溶胶钙（[Ca 2 +]cyt）升高的刺激而升高。与此相反，强光和外源性过氧化氢（H2 O2）诱导大，持续的[Ca 2 +]strelevations，不复制在胞质溶胶。利用荧光H2 O2传感器roGFP 2-氧化剂受体过氧化物酶1（Orp 1）进行的测量表明，这些刺激诱导的[Ca 2 +]流对应于叶绿体中H2 O2的积累。[Ca2+]strelevations也诱导加入甲基紫精，它产生超氧化物的叶绿体，并通过处理，破坏非光化学淬灭（NPQ）。研究结果表明，硅藻产生特定的[Ca 2 +]strelevations响应于强光和氧化应激，可能会调节钙敏感成分的光保护和其他调节途径的活性。
Diatoms are a group of silicified algae that play a major role in marine and freshwater ecosystems. Diatom chloroplasts were acquired by secondary endosymbiosis and exhibit important structural and functional differences from the primary plastids of land plants and green algae. Many functions of primary plastids, including photoacclimation and inorganic carbon acquisition, are regulated by calcium-dependent signaling processes. Calcium signaling has also been implicated in the photoprotective responses of diatoms; however, the nature of calcium elevations in diatom chloroplasts and their wider role in cell signaling remains unknown. Using genetically encoded calcium indicators, we find that the diatomPhaeodactylum tricornutumexhibits dynamic calcium elevations within the chloroplast stroma. Stromal calcium ([Ca2+]str) acts independently from the cytosol and is not elevated by stimuli that induce large cytosolic calcium ([Ca2+]cyt) elevations. In contrast, high light and exogenous hydrogen peroxide (H2O2) induce large, sustained [Ca2+]strelevations that are not replicated in the cytosol. Measurements using the fluorescent H2O2sensor roGFP2-Oxidant Receptor Peroxidase 1 (Orp1) indicate that [Ca2+]strelevations induced by these stimuli correspond to the accumulation of H2O2in the chloroplast. [Ca2+]strelevations were also induced by adding methyl viologen, which generates superoxide within the chloroplast, and by treatments that disrupt nonphotochemical quenching (NPQ). The findings indicate that diatoms generate specific [Ca2+]strelevations in response to high light and oxidative stress that likely modulate the activity of calcium-sensitive components in photoprotection and other regulatory pathways.
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影响因子：
16.6
作者：
Hochmal AK;Zinzius K;Charoenwattanasatien R;Gäbelein P;Mutoh R;Tanaka H;Schulze S;Liu G;Scholz M;Nordhues A;Offenborn JN;Petroutsos D;Finazzi G;Fufezan C;Huang K;Kurisu G;Hippler M
通讯作者：
Hippler M
影响因子：
2.1
作者：
Boron, WF
通讯作者：
Boron, WF
影响因子：
4.6
作者：
Kanemaru, Kazunori;Suzuki, Junji;Iino, Masamitsu
通讯作者：
Iino, Masamitsu
影响因子：
11.6
作者：
Allorent, Guillaume;Tokutsu, Ryutaro;Finazzi, Giovanni
通讯作者：
Finazzi, Giovanni
DOI：
10.1002/bmb.2003.494031060265
发表时间：
2003-11-01
影响因子：
1.4
作者：
Dean, RL;Miskiewicz, E
通讯作者：
Miskiewicz, E