Wax crystal-sparse leaf 3 encoding a β-ketoacyl-CoA reductase is involved in cuticular wax biosynthesis in rice
Wax crystal-sparse leaf 3 encoding a β-ketoacyl-CoA reductase is involved in cuticular wax biosynthesis in rice
复制标题
编码β-酮脂酰辅酶A还原酶的蜡晶稀疏叶3参与水稻角质层蜡生物合成
DOI：
10.1007/s00299-016-1983-1
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发表时间：
2016-08-01
影响因子：
6.2
通讯作者：
Wan, Jianmin
中科院分区：
文献类型：
--
作者：
Gan, Lu;Wang, Xiaole;Wan, Jianmin
WSL 3编码水稻中的β-酮脂酰辅酶A还原酶（KCR），与酵母中的YBR 159 w类似，是VLCFA生物合成和叶蜡积累所必需的。植物表面的表皮蜡限制非气孔水分流失，保护植物免受灰尘沉积，并对病原体感染施加物理屏障。我们确定了一个缺蜡的水稻突变体，蜡晶稀疏叶3（wsl 3），它表现出多效性表型，包括减少上表皮蜡晶在叶表面和改变蜡组成。基于图位的克隆表明，突变体中的缺陷是由编码β-酮脂酰辅酶A还原酶（KCR）的基因中两个相邻的单核苷酸变化引起的，该基因催化脂肪酸延伸反应的第二步。通过遗传互补进一步证实了WSL 3的身份。在烟草原生质体中的荧光蛋白标记的WSL 3的瞬时测定表明，WSL 3定位于内质网，在细胞中的脂肪酸延伸的隔室。定量PCR和组织化学染色表明WSL 3在组织中普遍表达。WSL 3的RNA干扰引起模仿wsl 3突变体的表型。当WSL 3和拟南芥脂肪酸延伸1（FAE 1）在酵母ybr 159 w Delta突变株中共表达时，检测到极长链脂肪酸（VLCFA）20：0和22：0，或20：1 Delta（11）和22：1 Delta（13）。结果表明，WSL 3通过参与VLCFA的伸长来影响水稻角质层蜡质的产生。
WSL3 encodes beta-ketoacyl-CoA reductase (KCR) in rice, in a similar way to YBR159w in yeast, and is essential for VLCFA biosynthesis and leaf wax accumulation.Cuticular waxes on plant surfaces limit non-stomatal water loss, protect plants against deposits of dust and impose a physical barrier to pathogen infection. We identified a wax-deficient mutant of rice, wax crystal-sparse leaf 3 (wsl3), which exhibits a pleiotropic phenotype that includes reduced epicuticular wax crystals on the leaf surface and altered wax composition. Map-based cloning demonstrated that defects in the mutant were caused by two adjacent single-nucleotide changes in a gene encoding beta-ketoacyl-CoA reductase (KCR) that catalyzes the second step of the fatty acid elongation reaction. The identity of WSL3 was further confirmed by genetic complementation. Transient assays of fluorescent protein-tagged WSL3 in tobacco protoplasts showed that WSL3 localizes to the endoplasmic reticulum, the compartment of fatty acid elongation in cells. Quantitative PCR and histochemical staining indicated that WSL3 is universally expressed in tissues. RNA interference of WSL3 caused a phenotype that mimicked the wsl3 mutant. Very long-chain fatty acids (VLCFAs) 20:0 and 22:0, or 20:1 Delta(11) and 22:1 Delta(13), were detected when WSL3 and Arabidopsis fatty acid elongation 1 (FAE1) were co-expressed in a yeast ybr159w Delta mutant strain. Our results indicated that WSL3 affects rice cuticular wax production by participating in VLCFA elongation.