Centre de Recherche en Horticulture, Département de phytologie, Université Laval, Pavillon des Services, 2440 boul, Hochelaga, Québec, QC G1V 0A6, Canada.
BMC Plant Biol. 2012 Nov 1;12:198. doi: 10.1186/1471-2229-12-198.
Studies reported unintended pleiotropic effects for a number of pesticidal proteins ectopically expressed in transgenic crops, but the nature and significance of such effects in planta remain poorly understood. Here we assessed the effects of corn cystatin II (CCII), a potent inhibitor of C1A cysteine (Cys) proteases considered for insect and pathogen control, on the leaf proteome and pathogen resistance status of potato lines constitutively expressing this protein.
The leaf proteome of lines accumulating CCII at different levels was resolved by 2-dimensional gel electrophoresis and compared with the leaf proteome of a control (parental) line. Out of ca. 700 proteins monitored on 2-D gels, 23 were significantly up- or downregulated in CCII-expressing leaves, including 14 proteins detected de novo or up-regulated by more than five-fold compared to the control. Most up-regulated proteins were abiotic or biotic stress-responsive proteins, including different secretory peroxidases, wound inducible protease inhibitors and pathogenesis-related proteins. Accordingly, infection of leaf tissues by the fungal necrotroph Botryris cinerea was prevented in CCII-expressing plants, despite a null impact of CCII on growth of this pathogen and the absence of extracellular Cys protease targets for the inhibitor.
These data point to the onset of pleiotropic effects altering the leaf proteome in transgenic plants expressing recombinant protease inhibitors. They also show the potential of these proteins as ectopic modulators of stress responses in planta, useful to engineer biotic or abiotic stress tolerance in crop plants of economic significance.
研究报告称，在转基因作物中外源表达的许多杀虫剂蛋白存在意外的多效性效应，但这种效应在植物体内的性质和意义仍知之甚少。在这里，我们评估了玉米半胱氨酸蛋白酶抑制剂 II（CCII）对持续表达这种蛋白的马铃薯品系叶片蛋白质组和病原体抗性的影响。CCII 是一种有效的 C1A 半胱氨酸（Cys）蛋白酶抑制剂，可用于防治昆虫和病原体。
通过 2 维凝胶电泳分离并比较不同水平积累 CCII 的品系的叶片蛋白质组与对照（亲本）系的叶片蛋白质组。在 2-D 凝胶上监测的大约 700 种蛋白质中，有 23 种在 CCII 表达叶片中显著上调或下调，其中包括 14 种与对照相比新检测到或上调超过五倍的蛋白质。大多数上调的蛋白质是生物或非生物胁迫响应蛋白，包括不同的分泌过氧化物酶、伤口诱导蛋白酶抑制剂和与发病相关的蛋白。因此，尽管 CCII 对这种病原体的生长没有影响，且抑制剂没有细胞外 Cys 蛋白酶靶标，但 CCII 表达植物中的真菌坏死病原体 Botrytis cinerea 的叶片组织感染得到了预防。
这些数据表明，在表达重组蛋白酶抑制剂的转基因植物中，会出现改变叶片蛋白质组的多效性效应。它们还表明，这些蛋白质作为植物中外源应激反应调节剂具有潜力，可用于工程化具有经济意义的作物植物的生物或非生物胁迫耐受性。
