Novel mutations affecting leaf stearate content and plant size in Arabidopsis
Novel mutations affecting leaf stearate content and plant size in Arabidopsis
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DOI：
10.1007/s001220050504
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发表时间：
1997-06
影响因子：
5.4
通讯作者：
J. Lightner;E. Lark;D. James;J. Browse
中科院分区：
文献类型：
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作者：
J. Lightner;E. Lark;D. James;J. Browse
拟南芥的 fab2-1 突变体是一种极端矮化，是膜脂中硬脂酸盐 (18 : 0) 水平增加的直接结果。我们分离了一系列品系，其中第二位点抑制突变部分减轻了矮化表型。在所检查的所有四个抑制系中，更正常形态的恢复伴随着叶片 18 : 0 含量的减少。三个分离的抑制剂抑制叶子和种子中的高硬脂酸盐表型。其中一种抑制器 TW2-1 的作用仅限于叶子。还鉴定了 fab2 基因座上的第二个等位基因 fab2-2，并且该等位基因为纯合植物，其植物大小和 18 : 0 含量介于野生型拟南芥和 fab2-1 突变体之间。等位基因 atfab2 和抑制突变提供了总共 9 个基因型，对这些基因型进行分析以证明叶 18 : 0 含量（叶总脂肪酸的 0.7–19.6%）与植物尺寸减小（24–4 mm）之间存在明确的关系。这些结果说明了抑制分析在解决生物化学和植物生物学问题中的实用性。他们还表明，植物脂质组成的遗传控制比以前认识的更加复杂。
Thefab2-1mutant ofArabidopsisis an extreme dwarf as a direct result of an increase in the levels of stearate (18 : 0) in membrane lipids. We isolated a series of lines in which second-site suppressor mutations partly alleviate the dwarf phenotype. In all four of the suppressor lines examined, restoration of more normal morphology is accompanied by decreases in leaf 18 : 0 content. Three of the isolated suppressors suppress the high stearate phenotype in both leaves and seeds. The effects of one of the suppressors, TW2-1, is limited to the leaves. A second allele at thefab2locus,fab2-2, was also identified and plants homozygous for this allele where intermediate in both plant size and 18 : 0 content between wild-typeArabidopsisandfab2-1mutants. The alleles atfab2and the suppressor mutations provided a total of nine genotypes which were analyzed to demonstrate a clear-cut relationship between leaf 18 : 0 content (0.7–19.6% of total leaf fatty acids) and reductions in plant size (24–4 mm). These results illustrate the utility of suppressor analysis for addressing problems in biochemistry and plant biology. They also indicate that the genetic control of plant lipid composition is more complex than previously appreciated.