Photosynthetic carbon and nitrogen metabolism and the relationship between their metabolites and lipid peroxidation in dwarf bamboo (Fargesia rufa Yi) during drought and subsequent recovery
Photosynthetic carbon and nitrogen metabolism and the relationship between their metabolites and lipid peroxidation in dwarf bamboo (Fargesia rufa Yi) during drought and subsequent recovery
复制标题
干旱和恢复期间矮竹光合碳氮代谢及其代谢物与脂质过氧化的关系
DOI：
10.1007/s00468-015-1241-0
复制
发表时间：
2015-12-01
影响因子：
2.3
通讯作者：
Zhang, Lin
中科院分区：
文献类型：
--
作者：
Liu, Chenggang;Wang, Yanjie;Zhang, Lin
矮秆竹C、N代谢的差异调节提高了渗透调节能力，其代谢产物可能在干旱胁迫下对膜脂过氧化起保护作用，从而加速复水后的恢复。矮竹（Fargesia rufa Yi）是濒危大熊猫的主食，但干旱对竹类物种的影响及其恢复机制却知之甚少。本研究探讨了干旱和恢复后植物碳、氮代谢的响应及其与脂质过氧化的关系。干旱后，光化学可逆下调，但需要较长的恢复时间。由于淀粉酶活性的快速增加，淀粉的加速降解导致了仅在严重干旱胁迫的植物中，在干旱30天后，可溶性糖含量较高。蔗糖含量不受干旱的影响，因为相对增加的活性转化酶，蔗糖合成酶，蔗糖磷酸合成酶。随着硝酸盐浓度的增加与硝酸还原酶活性平行，铵（NH 4+）的生产增强干旱。此外，激活的谷氨酰胺合成酶/谷氨酸合成酶循环刺激NH 4+同化，同时加速可溶性蛋白质的水解，导致氨基酸的积累。复水后，碳代谢的重新平衡已逐渐开始，但仍观察到较强的N代谢。干旱15 d后MDA与淀粉、脯氨酸含量呈显著正相关，干旱30 d后MDA与可溶性糖、NSC、脯氨酸含量呈显著正相关。说明在不同干旱强度和干旱持续时间下，矮竹不仅可以通过不同方式调节自身的碳氮代谢，提高渗透调节能力，而且还可以利用自身不同的代谢产物对抗膜脂过氧化，从而加速复水后的恢复。
Differential regulations of C and N metabolism in dwarf bamboo improve the capacity of osmotic adjustment, and also their metabolites may play an important role for protection against membrane lipid peroxidation under drought, thus accelerating recovery after rewatering. Dwarf bamboo (Fargesia rufa Yi), is a staple food for the endangered giant panda, but little is known about the impact of drought on bamboo species and its recovery mechanism. This study investigated the response of carbon (C) and nitrogen (N) metabolism to drought and subsequent recovery, and the relationship of their metabolites with lipid peroxidation. Photochemistry was reversibly down-regulated after drought, but a longer recovery time is needed. The accelerated degradation of starch due to a rapid increase in amylase activity resulted in higher soluble sugar only in severe drought-stressed plants after 30 days of drought. Sucrose content was not affected by drought because of the relative increases in activities of invertase, sucrose synthase, and sucrose phosphate synthase. As nitrate concentration increased in parallel with nitrate reductase activity, ammonium (NH4+) production was enhanced by drought. Also, activated glutamine synthetase/glutamate synthase cycle stimulated NH4+ assimilation, while hydrolysis of soluble proteins was accelerated, resulting in accumulation of amino acids. After rewatering, re-balancing of C metabolism has gradually begun, but a stronger N metabolism was still observed. The notable positive correlations between MDA and the contents of starch and proline after 15 days of drought as well as between MDA and the contents of soluble sugar, NSC and proline after 30 days of drought were displayed. We conclude that dwarf bamboo may not only differently regulate its C and N metabolism to improve the capacity of osmotic adjustment but also employ its different metabolites protect against membrane lipid peroxidation under different intensities and duration of drought, thus accelerating its recovery after rewatering.