Istituto per la Protezione delle Piante, Consiglio Nazionale delle Ricerche, Via G. Amendola 165/A, Bari, Italy.
Appl Microbiol Biotechnol. 2011 Jun;90(6):1981-94. doi: 10.1007/s00253-011-3282-7. Epub 2011 May 4.
Expression profiles were identified in the fungus Pochonia chlamydosporia, a biological control agent of plant parasitic nematodes, through a cDNA-amplified fragment length polymorphism approach. Two isolates with different host ranges, IMI 380407 and IMI 331547, were assayed in conditions of saprotrophic-to-parasitic transition, through in vitro assays. Gene expression profiles from three different nutritional conditions and four sampling times were generated, with eggs of host nematodes Globodera pallida and Meloidogyne incognita. Expression of transcripts changed in RNA fingerprints obtained under different nutritional stresses (starvation in presence/absence of eggs, or rich growth media). Transcript derived fragments (TDFs) obtained from the expression profiles corresponded to 6,800 products. A subset was sequenced and their expression profile confirmed through RT PCR. A total of 57 TDFs were selected for further analysis, based on similarities to translated or annotated sequences. Genes expressed during egg parasitism for both IMI 380407 and IMI 331547 were involved in metabolic functions, cellular signal regulation, cellular transport, regulation of gene expression, DNA repair, and other unknown functions. Multivariate analysis of TDF expression showed three groups for IMI 380407 and one for IMI 331547, each characterized by expression of genes related to eggs parasitism. Common amplification profiles among TDF clusters from both isolates also reflected a pool of constitutive genes, not affected by the nutritional conditions and nematode associations, related to general metabolic functions. The differential expression of parasitism related genes suggest a network of induced/repressed products, playing a role in fungal signaling and infection, with partial overlaps in host infection and parasitism traits.
通过 cDNA 扩增片段长度多态性方法，在植物寄生线虫的生物防治剂盾壳霉（Pochonia chlamydosporia）中鉴定了表达谱。在体外测定中，对具有不同宿主范围的两个分离株 IMI 380407 和 IMI 331547 进行了测定。从三种不同营养条件和四个采样时间的基因表达谱中，生成了有宿主线虫金线虫（Globodera pallida）和南方根结线虫（Meloidogyne incognita）卵的表达谱。在不同营养胁迫下（有/无卵的饥饿或丰富的生长培养基），获得的 RNA 指纹图谱中表达的转录物发生了变化。从表达谱中获得的转录物衍生片段（TDFs）对应于 6800 种产物。根据与翻译或注释序列的相似性，选择了一部分进行 RT-PCR 确认其表达谱。基于与翻译或注释序列的相似性，选择了总共 57 个 TDF 进行进一步分析。在 IMI 380407 和 IMI 331547 中，在卵寄生期间表达的基因涉及代谢功能、细胞信号调节、细胞运输、基因表达调控、DNA 修复和其他未知功能。TDF 表达的多元分析显示，IMI 380407 有三组，IMI 331547 有一组，每组都有与卵寄生相关的基因表达。两个分离株的 TDF 簇之间的共同扩增图谱也反映了一组组成型基因，不受营养条件和线虫关联的影响，与一般代谢功能有关。寄生相关基因的差异表达表明，诱导/抑制产物的网络在真菌信号转导和感染中起作用，宿主感染和寄生特征有部分重叠。
