The SUGAR-DEPENDENT1 Lipase Limits Triacylglycerol Accumulation in Vegetative Tissues of Arabidopsis
The SUGAR-DEPENDENT1 Lipase Limits Triacylglycerol Accumulation in Vegetative Tissues of Arabidopsis
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DOI：
10.1104/pp.113.219840
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发表时间：
2013-07-01
期刊：
影响因子：
7.4
通讯作者：
Eastmond, Peter J.
中科院分区：
文献类型：
--
作者：
Kelly, Amelie A.;van Erp, Harrie;Eastmond, Peter J.
近年来，工程作物在其营养组织中产生三酰甘油（TAG）作为实现油产量阶跃变化的手段的前景引起了相当大的兴趣。在这里，我们表明，在拟南芥（拟南芥）脂肪酶突变体糖依赖1（sdp 1）的TAG水解中断导致大量的TAG积累在根和茎，但相对较低的TAG积累在叶中。sdp 1根中的TAG含量随着植物的年龄而增加，成熟时可达到干重的1%以上，比野生型增加50倍。sdp 1根中TAG的积累需要酰基辅酶A：二酰基甘油酰基转移酶1（DGAT 1）和磷脂酰胆碱：二酰基甘油酰基转移酶1，也可以通过提供外源糖强烈刺激。在组成型共表达WRINKLED 1和DGAT 1的转基因植物中，sdp 1也使根、茎和叶中TAG的积累加倍，其水平范围为干重的5%至8%。最后，提供3%（w/v）外源Suc可以进一步将这些转基因植物中的根TAG含量提高到干重的17%。这种TAG水平类似于许多植物物种中的种子组织，并确立了在营养组织中产生油的工程策略的功效，所述工程策略涉及同时操纵碳水化合物供应、脂肪酸合成、TAG合成以及TAG分解。
There has been considerable interest recently in the prospect of engineering crops to produce triacylglycerol (TAG) in their vegetative tissues as a means to achieve a step change in oil yield. Here, we show that disruption of TAG hydrolysis in the Arabidopsis (Arabidopsis thaliana) lipase mutant sugar-dependent1 (sdp1) leads to a substantial accumulation of TAG in roots and stems but comparatively much lower TAG accumulation in leaves. TAG content in sdp1 roots increases with the age of the plant and can reach more than 1% of dry weight at maturity, a 50-fold increase over the wild type. TAG accumulation in sdp1 roots requires both ACYL-COENZYME A: DIACYLGLYCEROL ACYLTRANSFERASE1 (DGAT1) and PHOSPHATIDYLCHOLINE: DIACYLGLYCEROL ACYLTRANSFERASE1 and can also be strongly stimulated by the provision of exogenous sugar. In transgenic plants constitutively coexpressing WRINKLED1 and DGAT1, sdp1 also doubles the accumulation of TAG in roots, stems, and leaves, with levels ranging from 5% to 8% of dry weight. Finally, provision of 3% (w/v) exogenous Suc can further boost root TAG content in these transgenic plants to 17% of dry weight. This level of TAG is similar to seed tissues in many plant species and establishes the efficacy of an engineering strategy to produce oil in vegetative tissues that involves simultaneous manipulation of carbohydrate supply, fatty acid synthesis, TAG synthesis, and also TAG breakdown.