Apoptosis-like programmed cell death in the grey mould fungus Botrytis cinerea: genes and their role in pathogenicity
Apoptosis-like programmed cell death in the grey mould fungus Botrytis cinerea: genes and their role in pathogenicity
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DOI：
10.1042/bst0391493
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发表时间：
2011-10-01
影响因子：
3.9
通讯作者：
Sharon, Amir
中科院分区：
文献类型：
--
作者：
Shlezinger, Neta;Doron, Adi;Sharon, Amir
近年来，已经鉴定了相当数量的人类凋亡基因的真菌同源物。然而，我们还远不能连接不同的片段，构建真菌凋亡调控网络的一级结构。为了更好地了解可用的真菌成分，我们生成了一个基于蛋白质序列和以域为中心的方法的自动搜索协议。我们用这个协议来搜索所有可用的真菌数据库的域和同源的人类凋亡蛋白。在所有已知的凋亡结构域中，只有BIR [杆状病毒IAP（凋亡抑制蛋白）重复]结构域在真菌中被发现。具有一个或两个BIR结构域的单一蛋白质存在于大多数（但不是全部）真菌物种中。我们从灰霉病菌Botrytis cinerea中分离出含BIR的蛋白，并确定其在细胞凋亡和致病性中的作用。我们还分离和分析了BcNMA，酵母NMA 11基因的同源物。BcBIR 1的部分敲除或过表达菌株证实了BcBIR 1是抗凋亡的，并且这种活性被分配给蛋白质的N ′-末端部分。植物感染试验表明，真菌在感染的早期阶段经历了大量的PCD（程序性细胞死亡）。进一步的研究表明，真菌的毒力与真菌科普植物诱导的PCD的能力完全相关。总之，我们的结果表明BcBir 1是B中PCD的主要调节因子。灰霉病和宿主诱导的PCD的适当调节是必不可少的发病机制，在这种和其他类似的真菌病原体。
A considerable number of fungal homologues of human apoptotic genes have been identified in recent years. Nevertheless, we are far from being able to connect the different pieces and construct a primary structure of the fungal apoptotic regulatory network. To get a better picture of the available fungal components, we generated an automatic search protocol that is based on protein sequences together with a domain-centred approach. We used this protocol to search all the available fungal databases for domains and homologues of human apoptotic proteins. Among all known apoptotic domains, only the BIR [baculovirus IAP (inhibitor of apoptosis protein) repeat] domain was found in fungi. A single protein with one or two BIR domains is present in most (but not all) fungal species. We isolated the BIR-containing protein from the grey mould fungus Botrytis cinerea and determined its role in apoptosis and pathogenicity. We also isolated and analysed BcNMA, a homologue of the yeast NMA11 gene. Partial knockout or overexpression strains of BcBIR1 confirmed that BcBir1 is anti-apoptotic and this activity was assigned to the N'-terminal part of the protein. Plant infection assays showed that the fungus undergoes massive PCD (programmed cell death) during early stages of infection. Further studies showed that fungal virulence was fully correlated with the ability of the fungus to cope with plant-induced PCD. Together, our result show that BcBir1 is a major regulator of PCD in B. cinerea and that proper regulation of the host-induced PCD is essential for pathogenesis in this and other similar fungal pathogens.