Mehli Lisbeth, Schaart Jan G, Kjellsen Trygve D, Tran Diem Hong, Salentijn Elma M J, Schouten Henk J, Iversen Tor-Henning
Plantebiosenteret, Department of Biology, NTNU, 7491 Trondheim, Norway.
Present address: Sør-Trøndelag University College, Department of Food Science, Trondheim, Norway.
New Phytol. 2004 Jul;163(1):99-110. doi: 10.1111/j.1469-8137.2004.01088.x.
• Polygalacturonase-inhibiting proteins (PGIPs) have been demonstrated to play a role in host defence in several plants. • The PGIP now cloned from strawberry (Fragaria × ananassa) showed a high degree of homology to other fruit PGIPs. The gene expression of strawberry PGIP was monitored in healthy leaves, flowers and fruit at different maturity stages. PGIP transcript levels were also analysed following fruit inoculation with the fungal pathogen Botrytis cinerea in strawberry cultivars displaying variation in susceptibility. • Healthy mature berries showed the highest constitutive PGIP gene expression levels compared with leaves, flowers and immature fruit, indicating that the gene is developmentally regulated. Among the cultivars studied ('Elsanta', 'Korona', 'Polka', 'Senga sengana', 'Tenira'), 'Polka' had the highest constitutive expression level of PGIP. After inoculation with B. cinerea, all five cultivars displayed a significant induction of PGIP gene expression, but the differences between them were not statistically significant. • The high induction of the PGIP gene after inoculation with B. cinerea indicates that PGIP has a role in defence of strawberry.
• 多聚半乳糖醛酸酶抑制蛋白（PGIPs）已被证明在多种植物的宿主防御中发挥作用。
• 目前从草莓（Fragaria × ananassa）中克隆出的PGIP与其他果实PGIP具有高度同源性。在健康的叶片、花朵以及不同成熟阶段的果实中监测草莓PGIP的基因表达。在用真菌病原体灰葡萄孢接种草莓品种果实后，分析了PGIP转录水平，这些草莓品种在易感性上存在差异。
• 与叶片、花朵和未成熟果实相比，健康成熟的浆果显示出最高的PGIP基因组成型表达水平，这表明该基因受发育调控。在所研究的品种（“Elsanta”、“Korona”、“Polka”、“Senga sengana”、“Tenira”）中，“Polka”的PGIP组成型表达水平最高。接种灰葡萄孢后，所有五个品种的PGIP基因表达均有显著诱导，但它们之间的差异无统计学意义。
• 接种灰葡萄孢后PGIP基因的高诱导表明PGIP在草莓防御中发挥作用。
