番茄 UVR8 基因对果实采后贮藏品质的影响

紫外线抗性位点8(UV resistance locus 8, UVR8)编码光受体蛋白,负责UV-B感知和信号转导,被认为参与调控其他的生理反应。文章对UVR8过表达和基因沉默植株的果实进行分析,结果表明:与对照组相比,UVR8过表达转基因番茄果实有着更长的贮藏期,其果实硬度显著高于野生型;对UVR8转基因番茄果实的过氧化氢酶(CAT)和过氧化物酶(POD)活性进行测定,结果发现过表达番茄果实的CAT、POD的酶活与野生型相比均显著提高,分别是野生型的2.5、2.3倍,而基因沉默番茄果实的酶活与野生型相比显著下降;同时对脂质过氧化指标的丙二醛(MDA)进行分析,表明每g过表达番茄果实中MDA物质的量有所降低,仅为野生型的1/2,而且每g基因沉默番茄果实中MDA物质的量与野生型相比明显升高。由以上结果可推测,UVR8基因在延长番茄果实采后贮藏期中发挥了作用。

UV resistance locus 8(UVR8) encodes a photoreceptor protein, which is responsible for UV-B sensing and signal transduction, and is believed to be involved in the regulation of other physiological reactions. In this work, the fruits of UVR8 overexpression and gene-silenced plants were analyzed, and it showed that compared with the control group, the UVR8 overexpressed transgenic tomato (Solanum lycopersicum) fruits had a longer storage period, and the fruit hardness was significantly higher than that of the wild type. The catalase(CAT) and peroxidase(POD) activities of UVR8 transgenic tomato fruits were measured, and the results showed that the activities of CAT and POD in overexpressed tomato fruits were significantly higher than those in the wild type, which were 2.5 and 2.3 times higher than those in the wild type, respectively; while the activities of CAT and POD in gene-silenced tomato fruits were significantly lower than those in the wild type. The analysis of malondialdehyde(MDA), which is an indicator of lipid peroxidation, showed that the content of MDA per gram of overexpressed tomato fruits was reduced, which was only half of that of the wild type, and the content of MDA per gram of gene-silenced tomato fruits was significantly higher than that of the wild type. It could be inferred from the above results that the UVR8 gene played a role in prolonging the postharvest storage period of tomato fruits.