Department of Plant Pathology, Washington State University, Pullman, WA 99164 6430, USA.
Plant Sci. 2013 Mar;201-202:98-107. doi: 10.1016/j.plantsci.2012.11.011. Epub 2012 Dec 5.
A DNase released from the fungal pathogen of bean, Fusarium solani f. sp. phaseoli (Fsph), was previously shown to signal the activation of total disease resistance and activate pathogenesis-related (PR) genes in pea. Data in the current study which used the pea-endocarp model to research non-host resistance, indicated that DNase released by Verticillium dahliae (Vd), pathogenic on potato also has non-host resistance-inducing capabilities in peas. Other strains of Vd that release DNase are pathogenic on other plant species. DNase catalytic activity was also released from representative genera of other pathogenic fungi. Purified VdDNase induced pisatin and pea gene DRR49 (PR-10 gene) in pea endocarp tissue. VdDNase reduced the in vitro growth of Vd but completely inhibited that of F. solani f. sp. pisi (Fspi) and a Colletotrichum pathogen of potato. VdDNase (2 units) applied to pea endocarp tissue both broke resistance to Fsph and increased resistance to Fspi. Pea DNA damage generated both by the VdDNase enzyme and the intact Vd spores indicated that the host DNA alteration is a component of the non-host resistance response (innate immunity). These data support the previously reported inductive potential of fungal DNase and further implicate fungal DNases as signals in activating non-host resistance responses.
一种从豆类病原菌尖孢镰刀菌（Fusarium solani f. sp. phaseoli，Fsph）中释放的 DNase 先前被证明可激活豌豆的总抗病性并激活病程相关（PR）基因。本研究使用豌豆内种皮模型来研究非寄主抗性的数据表明，尖孢镰刀菌（Verticillium dahliae，Vd）释放的 DNase 也具有在豌豆中诱导非寄主抗性的能力，Vd 对马铃薯致病，其他致病的 Vd 菌株也会在其他植物物种上致病。其他致病真菌的代表性属也释放了具有催化活性的 DNase。纯化的 VdDNase 诱导豌豆内种皮组织中豆甾醇和 pea 基因 DRR49（PR-10 基因）。VdDNase 抑制 Vd 的体外生长，但完全抑制 F. solani f. sp. pisi（Fspi）和一种马铃薯炭疽病菌的生长。将 2 单位的 VdDNase 应用于豌豆内种皮组织，既能打破对 Fsph 的抗性，又能增强对 Fspi 的抗性。VdDNase 酶和完整的 Vd 孢子产生的豌豆 DNA 损伤表明，宿主 DNA 改变是非寄主抗性反应（先天免疫）的一个组成部分。这些数据支持先前报道的真菌 DNase 的诱导潜力，并进一步表明真菌 DNases 作为激活非寄主抗性反应的信号。
