Dual effects of transgenic Brassica napus overexpressing CS gene on tolerances to aluminum toxicity and phosphorus deficiency
Dual effects of transgenic Brassica napus overexpressing CS gene on tolerances to aluminum toxicity and phosphorus deficiency
复制标题
过表达CS基因的转基因甘蓝型油菜对铝毒和磷缺乏耐受性的双重影响
DOI：
10.1007/s11104-012-1289-1
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发表时间：
2012
期刊：
影响因子：
4.9
通讯作者：
Fangsen Xu
中科院分区：
文献类型：
--
作者：
Jiaojiao Kou;Lei Shi;Chunyu Zhang;Fangsen Xu
背景与目的低磷(P)的生物有效性和铝(Al)的毒性是酸性土壤上植物生长的两大制约因素。为了提高甘蓝型油菜对铝毒和缺磷的耐受性，我们建立了高表达铜绿假单胞菌柠檬酸合成酶(CS)基因的油菜(Brassica Napus Cv Westar)转基因油菜品系，并研究了CS基因在油菜中的高表达对提高对这两种胁迫的耐性的影响。方法采用水培和土壤培养相结合的方法，对转基因油菜(Brassica Napus Cv Westar)进行载体构建和植物转化、分子鉴定、细胞外和细胞内柠檬酸和苹果酸浓度的测定、酶活性和基因表达分析以及耐铝性和磷的获取试验。这些增加可能归因于在铝胁迫下转基因植株在TCA循环中CS、苹果酸脱氢酶(MDH)和磷酸烯醇式丙酮酸羧化酶(PEPC)活性的提高以及BnALMT和BnMATE的表达。初生根伸长和铝处理时间延长(10天)试验表明，转基因品系的耐铝性增强。此外，当它们生长在缺磷条件下时，它们的柠檬酸和苹果酸分泌量增加。此外，转基因株系对缺磷胁迫的反应显著高于野生型。土壤培养试验表明，以FePO4为唯一磷源时，转基因油菜植株对土壤中磷的吸收增加，地上部和种子中的磷积累量增加。结论CS基因在甘蓝型油菜中的过表达不仅导致柠檬酸合成和分泌增加，而且还改变了苹果酸代谢，从而提高了转基因植株对铝胁迫和缺磷的耐受性。这些发现进一步揭示了CS基因过表达对植物铝毒和缺磷的双重影响。
Background and aimsLow phosphorus (P) bioavailability and aluminum (Al) toxicity are two major constraints to plant growth in acid soil. To improve the tolerance of Brassica napus to Al toxicity and P deficiency, we generated transgenic canola (Brassica napus cv Westar) lines overexpressing a Pseudomonas aeruginosa citrate synthase (CS) gene and then investigated the effects of CS gene overexpressing in canola on enhancing tolerance to the two constraints.MethodsThe vector construction and plant transformation, molecular identification, estimation of extracellular and cellular citrate and malate concentrations, enzyme activity and gene expression analyse and Al tolerance and P acquisition assays were conducted using both hydroponics and soil culturing in the study.ResultsBoth the root citrate and malate concentrations and their exudations in the two transgenic lines significantly increased compared with wild type (WT) following exposure to Al. These increases may be attributed to higher activities of the CS, malate dehydrogenase (MDH) and phosphoenolpyruvate carboxylase (PEPC) enzymes in the TCA cycle and the expression of BnALMT and BnMATE in the transgenic plants following Al exposure. The primary root elongation and prolonged Al treatment (10 days) experiments revealed that the transgenic lines displayed enhanced levels of Al tolerance. In addition, they showed enhanced citrate and malate exudation when grown in P-deficient conditions. Moreover, the enzyme activities of the transgenic lines were significantly higher compared with WT in response to P-deficient stress. The soil culture experiment showed that the transgenic lines possessed improved P uptake from the soil and accumulated more P in their shoots and seeds when FePO4 was used as the sole P source.ConclusionsThese results indicate that the overexpression of the CS gene in B. napus not only leads to increased citrate synthesis and exudation but also changes malate metabolism, which confers improved tolerances to Al toxicity and P deficiency in the transgenic plants. These findings provide further insight into the dual effects of CS gene overexpression on Al toxicity and P deficiency in plants.
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DOI：
10.2136/sssabookser3.3ed
发表时间：
1990
期刊：
--
影响因子：
--
作者：
R. Westerman
通讯作者：
R. Westerman
影响因子：
7.4
作者：
Ligaba, Ayalew;Katsuhara, Maki;Matsumoto, Hideaki
通讯作者：
Matsumoto, Hideaki
DOI：
10.1007/s11240-011-9963-1
发表时间：
2011-05
期刊：
Plant Cell, Tissue and Organ Culture (PCTOC)
影响因子：
--
作者：
N. Martins;S. Gonçalves;T. Palma;A. Romano
通讯作者：
N. Martins;S. Gonçalves;T. Palma;A. Romano
影响因子：
7.4
作者：
DELHAIZE, E;RYAN, PR;RANDALL, PJ
通讯作者：
RANDALL, PJ
DOI：
10.3891/acta.chem.scand.17s-0129
发表时间：
1963
期刊：
Acta Chemica Scandinavica
影响因子：
--
作者：
P. Srere;H. Brazil;L. Gonen;Mark Takahashi
通讯作者：
P. Srere;H. Brazil;L. Gonen;Mark Takahashi