van den Heuvel K J, Hulzink J M, Barendse G W, Wullems G J
Department of Molecular Plant Physiology, University of Nijmegen, Toernooiveld 1, 6525 ED Nijmegen, Netherlands.
J Exp Bot. 2001 Jul;52(360):1427-36. doi: 10.1093/jexbot/52.360.1427.
A flower specific cDNA, tgas118, has been isolated after differential screening of a gib-1 anther cDNA library of Lycopersicon esculentum. The corresponding mRNA was present in all tissues analysed. Northern blot analysis revealed that in wild-type tomato the gene was predominantly expressed throughout flower development, while in the gibberellin (GA)-deficient mutant of tomato (gib-1) the abundance declined. Treatment of the mutant with GA resulted in an accumulation of the tgas118 mRNA within hours in leaf and bud tissues. In the leaf, GA1, GA3 and GA9 were effective in enhancing the expression while GA4 was not. In addition to GA, wounding and dehydration also increased the accumulation of tgas118 mRNA in leaf tissue. In situ hybridization showed that application of 50 ng GA3 bud(-1) induced a similar spatial expression of the tgas118 mRNA in gib-1 buds 24 h post treatment to that found in wild-type flower buds. The deduced TGAS118 protein displays up to 77% similarity with defensins and as its expression is up-regulated by stimuli such as wounding it is proposed that it may play a role in protection against pathogens.
通过对番茄（Lycopersicon esculentum）gib-1花药cDNA文库进行差异筛选，分离出了一个花特异性cDNA，tgas118。在所有分析的组织中均存在相应的mRNA。Northern印迹分析表明，在野生型番茄中，该基因在整个花发育过程中主要表达，而在番茄赤霉素（GA）缺陷型突变体（gib-1）中，其丰度下降。用GA处理突变体，数小时内叶和芽组织中tgas118 mRNA就会积累。在叶中，GA1、GA3和GA9能有效增强表达，而GA4则不能。除了GA，创伤和脱水也会增加叶组织中tgas118 mRNA的积累。原位杂交显示，处理后24小时，在gib-1芽中施加50 ng GA3芽（-1）诱导的tgas118 mRNA空间表达与野生型花芽中的相似。推导的TGAS118蛋白与防御素的相似性高达77%，由于其表达受创伤等刺激上调，推测它可能在抵御病原体方面发挥作用。
