期刊
JOURNAL OF EXPERIMENTAL BOTANY
卷 64, 期 5, 页码 1357-1366出版社
OXFORD UNIV PRESS
DOI: 10.1093/jxb/ers397
关键词
Chlorophyll a fluorescence; GSNO; guard cell; Microscopy-PAM; nitric oxide; non-photochemical quenching; photochemical quenching; Vicia faba
资金
- Hungarian Research Foundation [OTKA 81471]
- European Union
- European Social Fund
- [TAMOP-4.2.2/B-10/1-2010-0012]
Nitric oxide (NO) is one of the key elements in the complex signalling pathway leading to stomatal closure by inducing reversible protein phosphorylation and Ca-2 release from intracellular stores. As photosynthesis in guard cells also contributes to stomatal function, the aim of this study was to explore the potential role of NO as a photosynthetic regulator. This work provides the first description of the reversible inhibition of the effect of NO on guard cell photosynthetic electron transport. Pulse amplitude modulation (PAM) chlorophyll fluorescence measurements on individual stomata of peeled abaxial epidermal strips indicated that exogenously applied 450nM NO rapidly increases the relative fluorescence yield, followed by a slow and constant decline. It was found that NO instantly decreases photochemical fluorescence quenching coefficients (qP and qL), the operating quantum efficiency of photosystem II ((PSII)), and non-photochemical quenching (NPQ) to close to zero with different kinetics. NO caused a decrease in NPQ, which is followed by a slow and continuous rise. The removal of NO from the medium surrounding the epidermal strips using a rapid liquid perfusion system showed that the effect of NO on qP and (PSII), and thus on the linear electron transport rate through PSII (ETR), is reversible, and the constant rise in NPQ disappears, resulting in a near steady-state value. The reversible inhibition by NO of the ETR could be restored by bicarbonate, a compound known to compete with NO for one of the two coordination sites of the non-haem iron (II) in the Q(A)Fe(2)Q(B) complex.
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