GROWTH AND DEVELOPMENT OF THE AXR1 MUTANTS OF ARABIDOPSIS
GROWTH AND DEVELOPMENT OF THE AXR1 MUTANTS OF ARABIDOPSIS
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DOI：
10.1105/tpc.2.11.1071
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发表时间：
1990-11-01
期刊：
影响因子：
11.6
通讯作者：
ESTELLE, M
中科院分区：
文献类型：
--
作者：
LINCOLN, C;BRITTON, JH;ESTELLE, M
我们已经恢复了八个新的生长素抗性品系的拟南芥携带突变的AXR 1基因。这8个品系，连同先前报告中描述的12个品系，定义了至少5个不同的axr 1等位基因。所有突变株系具有相似的表型。缺陷包括植株高度、根向地性、下胚轴伸长和育性降低。突变株axr 1 -3对生长素的抗性低于其它突变株，且形态异常较轻。这种相关性表明，形态缺陷是生长素作用缺陷的结果。为了确定突变体植物的形态改变是否与细胞大小或组织结构的变化相关，使用扫描电子显微镜检查组织切片。在野生型和突变型组织之间没有观察到细胞大小的明显差异。然而，突变体茎的维管束被发现是不太好分化比野生型茎。通过用生长素溶液喷洒植物来测定莲座期植物的生长素敏感性。发现突变体roxanthus比野生型roxanthus对外源施加的生长素的敏感性显著降低，表明AXR 1基因在植物的地上部分起作用。我们的研究表明，AXR 1基因是所需的生长素行动在大多数，如果不是所有的植物组织，并在植物发育中发挥重要作用。连锁研究表明，该基因位于1号染色体上，距离最近的限制性片段长度多态性约2厘摩。
We have recovered eight new auxin-resistant lines of Arabidopsis that carry mutations in the AXR1 gene. These eight lines, together with the 12 lines described in a previous report, define at least five different axr1 alleles. All of the mutant lines have a similar phenotype. Defects include decreases in plant height, root gravitropism, hypocotyl elongation, and fertility. Mutant line axr1-3 is less resistant to auxin than the other mutant lines and has less severe morphological abnormalities. This correlation suggests that the morphological defects are a consequence of a defect in auxin action. To determine whether the altered morphology of mutant plants is associated with changes in cell size or tissue organization, tissue sections were examined using scanning electron microscopy. No clear differences in cell size were observed between wild-type and mutant tissues. However, the vascular bundles of mutant stems were found to be less well differentiated than those in wild-type stems. The auxin sensitivity of rosette-stage plants was determined by spraying plants with auxin solutions. Mutant rosettes were found to be significantly less sensitive to exogenously applied auxin than wild-type rosettes, indicating that the AXR1 gene functions in aerial portions of the plant. Our studies suggest that the AXR1 gene is required for auxin action in most, if not all, tissues of the plant and plays an important role in plant development. Linkage studies indicate that the gene is located on chromosome 1 approximately 2 centiMorgans from the closest restriction fragment length polymorphism.