Identification of a putative stearoyl acyl-carrier-protein desaturase gene from Saussurea involucrata
Identification of a putative stearoyl acyl-carrier-protein desaturase gene from Saussurea involucrata
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风毛菊中假定的硬脂酰酰基载体蛋白去饱和酶基因的鉴定
DOI：
10.1007/s10535-015-0487-0
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发表时间：
2015-06-01
影响因子：
1.5
通讯作者：
Zhu, J-B.
中科院分区：
文献类型：
--
作者：
Liu, H-L.;Shen, H-T.;Zhu, J-B.
雪莲。吉珥。耐包括寒冷在内的严重非生物胁迫，膜脂肪酸去饱和水平与其冷驯化有关。我们发现并鉴定了硬脂酰酰基载体蛋白去饱和酶（sikSACPD）的全长cDNA，其编码一个由396个氨基酸组成的蛋白。对SikSACPD蛋白的序列比对表明，该蛋白与红花（Carthamus tinctorius）和向日葵（Helianthus annuus）的sacpd蛋白同源性分别为91%和86%。半定量RT-PCR结果显示，随着温度从20℃降低到−10℃，sikSACPD在珙桐叶片中的表达增加。利用根癌农杆菌将脂肪酸生物合成2 (FAB2):SikSACPD和FAB2:FAB2构建物转化烟草，研究转基因烟草对冷冻胁迫的抗性和脂肪酸组成。FAB2:SikSACPD转基因植株对冰冻胁迫的抗性略高于野生型和FAB2:FAB2转基因植株。在低温胁迫下，SikSACPD转基因烟草叶片中油酸（C18:1）的含量比非转基因烟草增加了约5% ~ 20%。这项研究表明，SikSACPD基因在烟草中表达时，与在非转基因烟草中观察到的相比，具有更高的耐寒性。因此，该基因可能是增强其他作物耐寒性的候选基因。
Saussurea involucrata Kar. et Kir. tolerates severe abiotic stresses including cold, and the level of membrane fatty acid desaturation is associated with its cold acclimation. We discovered and characterized a full-length cDNA of stearoyl acyl-carrier-protein desaturase (sikSACPD) which encodes a protein consisted of 396 amino acids. A sequence alignment of the SikSACPD protein showed that it shares 91 and 86 % identity with the SACPDs of Carthamus tinctorius and Helianthus annuus, respectively. Semi-quantitative RT-PCR showed that the expression of sikSACPD increased in S. involucrata leaves as the temperature decreased from 20 to −10 °C. Agrobacterium tumefaciens was used to transform fatty acid biosynthesis 2 (FAB2):SikSACPD and FAB2:FAB2 constructs into tobacco to investigate resistance to a freezing stress and fatty acid composition of the transgenic plants. The FAB2:SikSACPD transgenic plants showed a slightly more resistance to the freezing stress than the FAB2:FAB2 transgenic plants and the wild-type. The proportion of oleic acid (C18:1) in the leaves of SikSACPD transgenic tobacco increased from approximately 5 to 20 % compared with the leaves of non-transgenic tobacco when both were exposed to cold stress treatments. This study demonstrates that the SikSACPD transgene, when expressed in tobacco, conferred a higher cold tolerance in comparison with that observed in non-transgenic tobacco. Thus, this gene may be a candidate for enhancing cold tolerance in other crop plants.