Instituto de Botánica del Nordeste (IBONE-CONICET), Facultad de Ciencias Agrarias, Universidad Nacional del Nordeste, Sargento Cabral 2131, CC: 209, W3402BKG Corrientes, Argentina.
Unidad de Biotecnología 1 IIB-INTECh (CONICET), CC: 164, B7130IWA Chascomús, Argentina.
Plant Physiol Biochem. 2014 Mar;76:29-35. doi: 10.1016/j.plaphy.2013.12.018. Epub 2014 Jan 3.
The accumulation of putrescine (Put) and increased arginine decarboxylase (ADC, EC 4.1.1.19) activity levels in response to osmotic stress has been reported; however, the biological meaning of this increase remains unclear. To obtain new insights into these questions, we studied the drought response of a transgenic Lotus tenuis line that expresses the oat ADC gene, which is driven by the stress-inducible pRD29A promoter. This line contains high levels of Put with no changes in spermidine and spermine contents, even under water deficits. Our results indicate that the biochemical and morphological responses to dehydration correlate with the Put level and provide evidence that Put controls the ABA content in response to drought by modulating ABA biosynthesis at the transcriptional level.
已有报道称，在应对渗透胁迫时腐胺（Put）的积累和精氨酸脱羧酶（ADC，EC 4.1.1.19）活性水平会增加；然而，这种增加的生物学意义尚不清楚。为了更深入地了解这些问题，我们研究了表达 oat ADC 基因的转基因 Lotus tenuis 系在干旱条件下的反应，该基因由应激诱导的 pRD29A 启动子驱动。即使在水分亏缺的情况下，该品系中腐胺的含量很高，而 spermidine 和 spermine 的含量没有变化。我们的结果表明，脱水的生化和形态反应与腐胺水平相关，并提供了证据表明腐胺通过在转录水平上调节 ABA 生物合成来控制 ABA 含量对干旱的响应。
