Dipartimento di Scienze del Suolo, Pianta, Ambiente e Produzioni Animali, Universita' degli Studi di Napoli Federico II, Via Università 100, Portici, Napoli 80055, Italy.
BMC Plant Biol. 2012 Jun 13;12:86. doi: 10.1186/1471-2229-12-86.
The fruit fly Bactrocera oleae is the primary biotic stressor of cultivated olives, causing direct and indirect damages that significantly reduce both the yield and the quality of olive oil. To study the olive-B. oleae interaction, we conducted transcriptomic and proteomic investigations of the molecular response of the drupe. The identifications of genes and proteins involved in the fruit response were performed using a Suppression Subtractive Hybridisation technique and a combined bi-dimensional electrophoresis/nanoLC-ESI-LIT-MS/MS approach, respectively.
We identified 196 ESTs and 26 protein spots as differentially expressed in olives with larval feeding tunnels. A bioinformatic analysis of the identified non-redundant EST and protein collection indicated that different molecular processes were affected, such as stress response, phytohormone signalling, transcriptional control and primary metabolism, and that a considerable proportion of the ESTs could not be classified. The altered expression of 20 transcripts was also analysed by real-time PCR, and the most striking differences were further confirmed in the fruit of a different olive variety. We also cloned the full-length coding sequences of two genes, Oe-chitinase I and Oe-PR27, and showed that these are wound-inducible genes and activated by B. oleae punctures.
This study represents the first report that reveals the molecular players and signalling pathways involved in the interaction between the olive fruit and its most damaging biotic stressor. Drupe response is complex, involving genes and proteins involved in photosynthesis as well as in the production of ROS, the activation of different stress response pathways and the production of compounds involved in direct defence against phytophagous larvae. Among the latter, trypsin inhibitors should play a major role in drupe resistance reaction.
地中海实蝇是橄榄的主要生物胁迫因子，对其造成直接和间接的损害，显著降低了橄榄的产量和橄榄油的质量。为了研究橄榄与地中海实蝇的相互作用，我们对其果实的分子反应进行了转录组学和蛋白质组学研究。采用抑制消减杂交技术和二维电泳/纳升电喷雾-线性离子阱-串联质谱联用技术，分别对参与果实应答的基因和蛋白进行了鉴定。
我们在有幼虫取食隧道的橄榄中鉴定出 196 个 EST 和 26 个差异表达的蛋白点。对鉴定出的非冗余 EST 和蛋白质集合的生物信息学分析表明，不同的分子过程受到影响，如应激反应、植物激素信号转导、转录调控和初级代谢，而且相当一部分 EST 无法分类。20 个转录本的表达变化也通过实时 PCR 进行了分析，在不同橄榄品种的果实中进一步证实了最显著的差异。我们还克隆了两个基因，Oe-几丁质酶 I 和 Oe-PR27 的全长编码序列，并证实它们是诱导型基因，被地中海实蝇刺伤激活。
本研究首次揭示了橄榄果实与最具破坏性的生物胁迫因子相互作用中涉及的分子参与者和信号通路。果实的应答是复杂的，涉及光合作用以及活性氧产生、不同应激应答途径的激活以及参与直接防御植食性幼虫的化合物的产生的基因和蛋白。其中，胰蛋白酶抑制剂在果实抵抗反应中应发挥主要作用。
