Laboratory of Fruit Genetics Engineering, The Institute of Enology and Viticulture, University of Yamanashi, Kofu, Yamanashi 400-0005, Japan.
Mol Biol Rep. 2012 Feb;39(2):911-7. doi: 10.1007/s11033-011-0816-0. Epub 2011 May 12.
We report the characterization of VvIAA19, an auxin/indole-3-acetic acid (Aux/IAA) protein, in grapevine (Vitis vinifera L.). VvIAA19 was expressed abundantly in berries. VvIAA19 transcription was rapidly increased at pre-anthesis and then decreased during fruit set. Before véraison, however, VvIAA19 gene expression was upregulated again and maximum expression was maintained until the end of ripening. Exogenous IAA did not induce VvIAA19 expression in grape leaves, suggesting that VvIAA19 might be auxin-nonresponsive. The overexpression of VvIAA19 in Arabidopsis thaliana had a notable effect on plant growth. Although no morphological changes were observed, transgenic Arabidopsis plants overexpressing VvIAA19 exhibited faster growth, including root elongation and floral transition, than the control plant, suggesting that the constitutive expression of VvIAA19 protein resulted in increased growth rates without any detectable harm. Taken together, we conclude that grape Aux/IAA19 protein is likely to play a crucial role as a plant growth regulator.
我们报告了葡萄（Vitis vinifera L.）中生长素/吲哚-3-乙酸（Aux/IAA）蛋白 VvIAA19 的特征。VvIAA19 在浆果中大量表达。VvIAA19 的转录在开花前迅速增加，然后在果实形成过程中减少。然而，在转色期之前，VvIAA19 基因的表达再次上调，并保持最大表达直到成熟结束。外源 IAA 不会诱导葡萄叶片中 VvIAA19 的表达，这表明 VvIAA19 可能对生长素不敏感。VvIAA19 在拟南芥中的过表达对植物生长有显著影响。尽管没有观察到形态变化，但过表达 VvIAA19 的转基因拟南芥植物的生长速度比对照植物快，包括根伸长和花发育，这表明 VvIAA19 蛋白的组成型表达导致生长速度增加，而没有任何可检测到的伤害。总之，我们得出结论，葡萄 Aux/IAA19 蛋白可能作为植物生长调节剂发挥重要作用。
