Chlamydomonas reinhardtii Exhibits De Facto Constitutive NPQ Capacity in Physiologically Relevant Conditions1[OPEN]
Chlamydomonas reinhardtii Exhibits De Facto Constitutive NPQ Capacity in Physiologically Relevant Conditions1[OPEN]
复制标题
莱茵衣藻在生理相关条件下表现出事实上的 NPQ 能力1[打开]
作者：
W. Nawrocki;Xin Liu;R. Croce
在模拟的强光、昼夜生长条件下，莱茵衣藻的光合机构通过非光化学猝灭表现出几乎结构性的光保护能力。光合器官必须能够承受超过其固碳能力的光照条件。光合生物产生了非光化学猝灭（NPQ），这是一个将多余的吸收光能作为热量耗散并限制活性氧和细胞损伤的过程。在绿色衣藻中，LHCSR色素结合蛋白是NPQ所必需的。这些复合物不是组成型存在于类囊体膜中;然而，在实验室条件下，它们的表达取决于细胞先前的高光暴露。为了研究NPQ的作用，我们测量了在中午具有高光峰的昼夜循环下生长的细胞。LHCSR存在，NPQ全天持续活性，可能是由于其在体内缓慢降解。这表明，在生理相关条件下，衣原体细胞准备立即激活光保护，就像维管植物一样。我们进一步揭示，在这些条件下，状态转换是完全功能性的，并且PsbS在一天中高度表达，这表明它可能比以前认为的更有影响力。
Under simulated high light, diel growth conditions, the photosynthetic apparatus of Chlamydomonas reinhardtii exhibits an almost constitutive photoprotection capacity through non-photochemical quenching. The photosynthetic apparatus must be able to withstand light conditions that exceed its capacity for carbon fixation. Photosynthetic organisms developed nonphotochemical quenching (NPQ), a process that dissipates excess absorbed light energy as heat and limits the production of reactive oxygen species and cellular damage. In the green alga Chlamydomonas reinhardtii, the LHCSR pigment-binding proteins are essential for NPQ. These complexes are not constitutively present in the thylakoid membranes; however, in laboratory conditions their expression depends on prior high light exposure of cells. To investigate the role of NPQ, we measured cells grown under a day-night cycle with a high light peak at mid-day. LHCSRs are present and NPQ is active consistently throughout the day, likely due to their slow degradation in vivo. This suggests that in physiologically relevant conditions, Chlamydomonas cells are prepared to immediately activate photoprotection, as is the case in vascular plants. We further reveal that state transitions are fully functional under these conditions and that PsbS is highly expressed throughout the day, suggesting it might have a more impactful role than previously thought.
影响因子：
4.8
作者：
Correa-Galvis, Viviana;Redekop, Petra;Jahns, Peter
通讯作者：
Jahns, Peter
影响因子：
7.4
作者：
Bergner, Sonja Verena;Scholz, Martin;Hippler, Michael
通讯作者：
Hippler, Michael