Defects in leaf carbohydrate metabolism compromise acclimation to high light and lead to a high chlorophyll fluorescence phenotype in Arabidopsis thaliana.
Defects in leaf carbohydrate metabolism compromise acclimation to high light and lead to a high chlorophyll fluorescence phenotype in Arabidopsis thaliana.
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DOI：
10.1186/1471-2229-12-8
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发表时间：
2012-01-16
影响因子：
5.3
通讯作者：
Häusler RE
中科院分区：
文献类型：
--
作者：
Schmitz J;Schöttler MA;Krueger S;Geimer S;Schneider A;Kleine T;Leister D;Bell K;Flügge UI;Häusler RE
我们已经研究了碳水化合物饥饿的驯化反应强光使用拟南芥双突变体强烈受损的光合产物出口的白天和黑夜的路径的影响。磷酸丙糖/磷酸转运蛋白基因的完全敲除突变体（TPT; tpt-2突变体）与（i）淀粉生物合成缺陷的突变体杂交（adg 1 - 1，pgm 1和pgi 1 - 1; ADP-葡萄糖焦磷酸化酶、质体磷酸葡萄糖变位酶和磷酸葡萄糖异构酶敲除）或（ii）淀粉动员（sex 1 - 3，葡聚糖水二激酶的敲除）以及（iii）从叶绿体中输出麦芽糖（mex 1 - 2）。所有的双突变体是可行的，从野生型在低光条件下生长时，没有区别，但-除了sex1 - 3/tpt-2-开发高叶绿素荧光（HCF）表型和生长迟缓时，在强光下生长。对adg1 - 1/tpt-2双突变体的类囊体蛋白的免疫印迹、蓝色天然凝胶电泳和77 K下的叶绿素荧光发射分析表明，HCF与两种光系统的质体编码核心蛋白的特异性减少有关（PSII组分细胞色素b559除外），而核编码触角（LHC）正常积累，但主要不附着在它们的光系统上。非耦合触角是暗适应植物HCF的主要原因。喂饲蔗糖或葡萄糖高光生长的adg1 - 1/tpt-2植物拯救的HCF和生长表型。升高的糖水平诱导葡萄糖-6-磷酸/磷酸转运子2（GPT2）的表达，其原则上可以补偿TPT中的缺陷。在GPT2（adg1 - 1/tpt-2/gpt2 - 1）中具有额外缺陷的三重突变体表现出与adg1 - 1/tpt-2双突变体相同的HCF和生长表型对糖喂养的响应，表明这种拯救独立于糖触发的GPT2诱导。我们认为胞质碳水化合物的利用率调节了A. thaliana.可以想象，叶绿体和细胞核之间关于光合作用基因的协调表达的强关系在碳水化合物饥饿的植物中被改变。因此，碳水化合物可能被认为是一种新的成分参与叶绿体到细胞核逆行信号，这方面将在未来的研究中解决。
We have studied the impact of carbohydrate-starvation on the acclimation response to high light using Arabidopsis thaliana double mutants strongly impaired in the day- and night path of photoassimilate export from the chloroplast. A complete knock-out mutant of the triose phosphate/phosphate translocator (TPT; tpt-2 mutant) was crossed to mutants defective in (i) starch biosynthesis (adg1-1, pgm1 and pgi1-1; knock-outs of ADP-glucose pyrophosphorylase, plastidial phosphoglucomutase and phosphoglucose isomerase) or (ii) starch mobilization (sex1-3, knock-out of glucan water dikinase) as well as in (iii) maltose export from the chloroplast (mex1-2). All double mutants were viable and indistinguishable from the wild type when grown under low light conditions, but - except for sex1-3/tpt-2 - developed a high chlorophyll fluorescence (HCF) phenotype and growth retardation when grown in high light. Immunoblots of thylakoid proteins, Blue-Native gel electrophoresis and chlorophyll fluorescence emission analyses at 77 Kelvin with the adg1-1/tpt-2 double mutant revealed that HCF was linked to a specific decrease in plastome-encoded core proteins of both photosystems (with the exception of the PSII component cytochrome b559), whereas nuclear-encoded antennae (LHCs) accumulated normally, but were predominantly not attached to their photosystems. Uncoupled antennae are the major cause for HCF of dark-adapted plants. Feeding of sucrose or glucose to high light-grown adg1-1/tpt-2 plants rescued the HCF- and growth phenotypes. Elevated sugar levels induce the expression of the glucose-6-phosphate/phosphate translocator2 (GPT2), which in principle could compensate for the deficiency in the TPT. A triple mutant with an additional defect in GPT2 (adg1-1/tpt-2/gpt2-1) exhibited an identical rescue of the HCF- and growth phenotype in response to sugar feeding as the adg1-1/tpt-2 double mutant, indicating that this rescue is independent from the sugar-triggered induction of GPT2. We propose that cytosolic carbohydrate availability modulates acclimation to high light in A. thaliana. It is conceivable that the strong relationship between the chloroplast and nucleus with respect to a co-ordinated expression of photosynthesis genes is modified in carbohydrate-starved plants. Hence carbohydrates may be considered as a novel component involved in chloroplast-to-nucleus retrograde signaling, an aspect that will be addressed in future studies.
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影响因子：
7.4
作者：
Athanasiou, Kleovoulos;Dyson, Beth C.;Johnson, Giles N.
通讯作者：
Johnson, Giles N.
DOI：
10.1111/j.1432-1033.1985.tb08692.x
发表时间：
1985-01-01
期刊：
EUROPEAN JOURNAL OF BIOCHEMISTRY
影响因子：
--
作者：
BASSI, R;PERUFFO, AD;GHISI, R
通讯作者：
GHISI, R
影响因子：
64.8
作者：
Bonardi, V;Pesaresi, P;Leister, D
通讯作者：
Leister, D
影响因子：
7.4
作者：
Eicks, M;Maurino, V;Fischer, K
通讯作者：
Fischer, K
影响因子：
11.4
作者：
Barros, Tiago;Royant, Antoine;Kuhlbrandt, Werner
通讯作者：
Kuhlbrandt, Werner