Coordination between xanthophyll cycle and antioxidant system in Sargassum thunbergii (Sargassaceae, Phaeophyta) in response to high light and dehydration stresses
Coordination between xanthophyll cycle and antioxidant system in Sargassum thunbergii (Sargassaceae, Phaeophyta) in response to high light and dehydration stresses
复制标题
马尾藻（马尾藻科，褐藻门）叶黄素循环和抗氧化系统之间的协调响应强光和脱水胁迫
DOI：
10.1007/s10811-016-0791-x
复制
发表时间：
2016-01
影响因子：
3.3
通讯作者：
Zhang Di
中科院分区：
文献类型：
--
作者：
Nan Guo Ning;Zhang Quan Sheng;Sheng Zi Tong;Zhang Di
研究了叶黄素循环（XC）和抗氧化系统在强光（HL）、脱水（DY）、先强光后脱水（HL-DY）以及HL + DY胁迫下对鼠尾藻光合机构光保护作用的差异贡献。4种胁迫均使脱环氧化态（DPS）和总抗氧化能力（T-AOC）上调。XC的去环氧化反应在应激暴露后较早发生，而抗氧化活性的显著变化需要相对较长的时间。在HL胁迫下，PSII光失活是显着的低PSII效率与有效量子产额和高激发压一起建议。同时，XC依赖的热耗散逐渐增加，达到一个高值。低水平的超氧自由基和过氧化氢表明低氧化应激伴随着低T-AOC。然而，DY处理过的样品表现出严重的氧化应激和高的解毒活性氧的能力，证明了高T-AOC，氧化型谷胱甘肽，和脱氢抗坏血酸。低DPS反映了XC的低活性。这些结果表明，XC对HL更敏感，而抗氧化系统对DY更敏感。当S.雷公藤叶片由HL转化为DY后，抗氧化系统活性的提高幅度大于XC脱环氧化。XC与抗氧化系统之间存在着协同作用，以响应不同的环境因子。此外，在HL-DY胁迫中，预光照降低了脱水过程中的光抑制和氧化胁迫的程度，表明强光照射可以使叶片更耐脱水。这一观察结果可以作为鉴定在潮间环境中具有更高竞争能力的物种的基础。
The differential contribution of the xanthophyll cycle (XC) and the antioxidant system to photoprotect the photosynthetic apparatus of Sargassum thunbergii to high light (HL), dehydration (DY), HL prior to DY (HL-DY), and HL in combination with DY stresses were investigated. Both de-epoxidation state (DPS) and total antioxidant capacity (T-AOC) were upregulated in response to the four kinds of stresses. The de-epoxidation of XC was engaged earlier in response to stress exposure while significant change in antioxidant activities took a relatively long time. Under HL stress, the PSII photoinactivation was significant as suggested by low maximum PSII efficiency together with effective quantum yield and high excitation pressure. Simultaneously, XC-dependent thermal dissipation increased progressively, reaching a high value. The low oxidative stress indicated by low levels of superoxide radical and hydrogen peroxide was accompanied with a low T-AOC. However, DY treated samples exhibited severe oxidative stress and high capacity to detoxify reactive oxygen species, as evidenced by the high T-AOC, oxidized glutathione, and dehydroascorbate. The low activity of XC was reflected by low DPS. These results indicated that XC was more sensitive to HL, while the antioxidant system was more sensitive to DY. When S. thunbergii blades were transferred to DY from HL, the enhancement of antioxidant system activity was greater than that of XC de-epoxidation. There exists coordination between XC and antioxidant system in response to varying environmental factors. In addition, as demonstrated in HL-DY stress, preillumination decreased the degree of photoinhibition and oxidative stress during dehydration, indicating that high light exposure could make the blades more tolerant to dehydration. This observation can be the bases to identify species that have developed with higher competitive abilities in adapting to the intertidal environment.
登录
查看更多内容
影响因子：
2.9
作者：
PATTERSON, BD;MACRAE, EA;FERGUSON, IB
通讯作者：
FERGUSON, IB
影响因子：
6.9
作者：
B. Logan;B. Demmig-Adams;W. W. Adams-W.;S. Grace
通讯作者：
B. Logan;B. Demmig-Adams;W. W. Adams-W.;S. Grace
影响因子：
5.3
作者：
Fernández-Marín B;Míguez F;Becerril JM;García-Plazaola JI
通讯作者：
García-Plazaola JI
影响因子：
3.7
作者：
K. Roháček
通讯作者：
K. Roháček
影响因子：
6.4
作者：
ADAMS, WW;DEMMIGADAMS, B
通讯作者：
DEMMIGADAMS, B