Schmelzer E., Kruger-Lebus S., Hahlbrock K.
Max-Planck-Institut fur Zuchtungsforschung, Abteilung Biochemie, Carl-von-Linne-Weg 10, D-5000 Koln 30, Federal Republic of Germany.
Plant Cell. 1989 Oct;1(10):993-1001. doi: 10.1105/tpc.1.10.993.
We analyzed the expression patterns of several pathogen defense-related genes in primary leaf buds of parsley by in situ RNA hybridization. Labeled antisense RNA probes were generated from seven selected cDNAs detecting transcripts from genes that are rapidly and strongly activated in cultured parsley cells upon treatment with fungal elicitor. These genes encode two enzymes of general phenylpropanoid metabolism, phenylalanine ammonia-lyase and 4-coumarate:CoA ligase, a furanocoumarin-specific bergaptol O-methyltransferase, one pathogenesis-related protein, and three less well characterized proteins, designated as ELI 3, ELI 5, and ELI 7. In uninfected tissue, phenylalanine ammonia-lyase and 4-coumarate:CoA ligase mRNA levels were high in epidermal cells, oil-duct epithelial cells, and cells of the developing xylem; bergaptol O-methyltransferase mRNA was confined to oil-duct epithelial cells; and the pathogenesis-related protein and ELI 3, ELI 5, and ELI 7 mRNAs were undetectable. All seven mRNAs accumulated transiently and locally around infection sites caused by the soybean-pathogenic fungus Phytophthora megasperma f. sp. glycinea, to which parsley is nonhost-resistant. The observed late appearance of bergaptol O-methyltransferase mRNA, as compared with all other mRNAs, is in accord with a similar relative timing of transient gene activation in elicitor-treated cell cultures. Sharp borders were observed between the infection center, where hypersensitive cell death had occurred in response to fungal penetration, the surrounding area of local gene activation, and the remainder of the tissue not showing any apparent response. Some of the genes were also activated, although less sharply localized, upon wounding of parsley leaves.
我们通过原位RNA杂交分析了欧芹初生叶芽中几个与病原体防御相关基因的表达模式。标记的反义RNA探针由七个选定的cDNA产生，这些cDNA检测的转录本来自在用真菌激发子处理后在培养的欧芹细胞中迅速且强烈激活的基因。这些基因编码一般苯丙烷类代谢的两种酶，苯丙氨酸解氨酶和4-香豆酸：辅酶A连接酶，一种呋喃香豆素特异性的补骨脂酚O-甲基转移酶，一种病程相关蛋白，以及三种特征不太明确的蛋白，命名为ELI 3、ELI 5和ELI 7。在未感染的组织中，苯丙氨酸解氨酶和4-香豆酸：辅酶A连接酶的mRNA水平在表皮细胞、油管上皮细胞和发育中的木质部细胞中较高；补骨脂酚O-甲基转移酶的mRNA局限于油管上皮细胞；而病程相关蛋白以及ELI 3、ELI 5和ELI 7的mRNA未检测到。所有七种mRNA在由大豆致病疫霉大豆专化型（欧芹对其无寄主抗性）引起的感染部位周围短暂且局部积累。与所有其他mRNA相比，观察到补骨脂酚O-甲基转移酶mRNA出现较晚，这与激发子处理的细胞培养物中瞬时基因激活的类似相对时间一致。在感染中心（因真菌穿透而发生超敏细胞死亡）、局部基因激活的周围区域和未显示任何明显反应的其余组织之间观察到清晰的边界。欧芹叶片受伤后，一些基因也被激活，尽管定位不太明显。
