NADPH Oxidases are involved in differentiation and pathogenicity in Botrytis cinerea
NADPH Oxidases are involved in differentiation and pathogenicity in Botrytis cinerea
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DOI：
10.1094/mpmi-21-6-0808
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发表时间：
2008-06-01
影响因子：
3.5
通讯作者：
Tudzynski, Paul
中科院分区：
文献类型：
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作者：
Segmueller, Nadia;Kokkelink, Leonie;Tudzynski, Paul
烟酰胺腺嘌呤二核苷酸（NADPH）氧化酶已被证明参与真菌的各种分化过程。我们研究了两种NADPH氧化酶在坏死营养型植物病原真菌灰葡萄孢中的作用。克隆并鉴定了bcnoxA和bcnoxB基因，其推导的氨基酸序列与真菌NADPH氧化酶具有很高的同源性。对NADPH氧化酶基因的单敲除和双敲除突变体的分析表明，bcnoxA和bcnoxB都参与了菌核的形成。这两种基因对致病性都有很大的影响：而bcnoxB突变体表现出延迟的原发性病变的形成，可能是由于穿透结构的形成受损，而bcnoxA突变体能够以与野生型相同的方式穿透宿主组织，但在定殖宿主组织方面要慢得多。双突变体表现出加性效应：它们在植物组织的渗透和定殖中是异常的，因此几乎是非致病性的。为了更详细地研究真菌Nox复合物的结构，对bcnoxR（编码哺乳动物p67（phox）的同源物，Nox复合物的调节亚基）进行功能表征。Delta bcnoxR突变体的表型与Delta bcnoxAB双突变体的表型相同，这提供了BcnoxR参与两种Bcnox酶的激活的证据。
Nicotinamide adenine dinucleotide (NADPH) oxidases have been shown to be involved in various differentiation processes in fungi. We investigated the role of two NADPH oxidases in the necrotrophic phytopathogenic fungus, Botrytis cinerea. The genes bcnoxA and bcnoxB were cloned and characterized; their deduced amino acid sequences show high homology to fungal NADPH oxidases. Analyses of single and double knock-out mutants of both NADPH oxidase genes showed that both bcnoxA and bcnoxB are involved in formation of sclerotia. Both genes have a great impact on pathogenicity: whereas bcnoxB mutants showed a retarded formation of primary lesions, probably due to an impaired formation of penetration structures, bcnoxA mutants were able to penetrate host tissue in the same way as the wild type but were much slower in colonizing the host tissue. Double mutants showed an additive effect: they were aberrant in penetration and colonization of plant tissue and, therefore, almost nonpathogenic. To study the structure of the fungal Nox complex in more detail, bcnoxR (encoding a homolog of the mammalian p67(phox), a regulatory subunit of the Nox complex) was functionally characterized. The phenotype of Delta bcnoxR mutants is identical to that of Delta bcnoxAB double mutants, providing evidence that BcnoxR is involved in activation of both Bcnox enzymes.