Lers A, Burd S, Lomaniec E, Droby S, Chalutz E
Department of Postharvest Science of Fresh Produce, The Volcani Center, Bet Dagan, Israel.
Plant Mol Biol. 1998 Apr;36(6):847-56. doi: 10.1023/a:1005996515602.
Exposure of harvested grapefruit to UV-C (254 nm) irradiation was previously found to induce resistance against the green mold decay caused by Penicillium digitatum. In order to gain insight into the mechanism of this UV-induced resistance we initiated a study for isolation of genes induced during this process. Using the differential display method we cloned cDNA representing an mRNA which is accumulated in grapefruit peel upon UV irradiation. Sequence analysis revealed that this cDNA represents a gene encoding for an isoflavone reductase-like protein and was termed IRL (isoflavone reductase-like). The grapefruit IRL protein sequence has high homology also to a novel family of other isoflavone reductase-like proteins present in few non-legume plants and whose function is not clear yet. The UV dose, and time following it, which lead to maximal accumulation of the IRL transcript were found to be similar to those leading to maximal induced resistance. The expression of the IRL gene was demonstrated to be induced also by wounding and pathogen infection.
先前发现，将采收后的葡萄柚暴露于UV-C（254纳米）辐射下，可诱导其对指状青霉引起的绿霉腐烂产生抗性。为深入了解这种紫外线诱导抗性的机制，我们启动了一项研究，旨在分离此过程中诱导表达的基因。利用差异显示法，我们克隆了代表一种mRNA的cDNA，该mRNA在紫外线照射后在葡萄柚果皮中积累。序列分析表明，此cDNA代表一个编码类异黄酮还原酶样蛋白的基因，被命名为IRL（类异黄酮还原酶样）。葡萄柚IRL蛋白序列与少数非豆科植物中存在的其他类异黄酮还原酶样蛋白的一个新家族也具有高度同源性，其功能尚不清楚。导致IRL转录本最大积累的紫外线剂量及其后的时间，与导致最大诱导抗性的剂量和时间相似。IRL基因的表达也被证明可由创伤和病原体感染诱导。
