Vital role for cyclophilin B (CypB) in asexual development, dimorphic transition and virulence of Beauveria bassiana
Vital role for cyclophilin B (CypB) in asexual development, dimorphic transition and virulence of Beauveria bassiana
复制标题
亲环蛋白 B (CypB) 在白僵菌无性发育、二态性转变和毒力中的重要作用
DOI：
10.1016/j.fgb.2017.05.004
复制
发表时间：
2017-08-01
影响因子：
3
通讯作者：
Feng, Ming-Guang
中科院分区：
文献类型：
--
作者：
Chu, Zhen-Jian;Sun, Huan-Huan;Feng, Ming-Guang
先前揭示了环糖蛋白B（CYPB）是Babassiana感染对鳞翅目害虫的转录组中许多推定的分泌蛋白之一。在这里，我们显示了CYPB在菌丝细胞壁和SEPTA中的主要定位及其在真菌昆虫病原体的体外和体内无性周期中的重要作用。 CYPB的删除在两种富培养基和30个具有不同碳或氮源不同的较低培养基的介质中降低了16-42％。缺失突变体在标准培养基上的分生体延迟，最终的分生孢子产量降低了47％，并伴随着分裂和分生孢子成熟所需的几个关键基因的剧烈转录本抑制。突变的分生孢子需要比野生型分生孢子在最佳25摄氏度时长10 h才能发芽50％。有趣的是，在海藻糖肽肉汤中培养突变分生孢子与昆虫血淋巴的模仿导致大孢子产量的降低83％，但只有生物质水平略有降低，表明菌丝向胚胎向胚胎的过渡性严重缺陷。从正常的角质层感染中针对梅洛尼亚氏菌的缺失突变体的LT50从野生型估计值延长至7.4 d。此外，在菌落生长过程中，缺失突变体对刚果红，Menadione，H2O2和热休克表现出高敏性，但对环孢菌素A和雷帕霉素的耐受性提高了。所有变化均通过靶向基因互补恢复。总体而言，CYPB参与了B. b. bassiana中的正常生长，空中分生物，分生孢子发芽，二态过渡，应激耐受性和致病性。
Cyclophilin B (CypB) was previously revealed as one of many putative secretory proteins in the transcriptome of Beauveria bassiana infection to a lepidopteran pest. Here we show a main localization of CypB in hyphal cell walls and septa and its essential role in the in vitro and in vivo asexual cycles of the fungal insect pathogen. Deletion of cypB reduced colony growth by 16-42% on two rich media and 30 scant media with different carbon or nitrogen sources. The deletion mutant suffered a delayed conidiation on a standard medium and a final 47% reduction in conidial yield, accompanied with drastic transcript depression of several key genes required for conidiation and conidial maturation. The mutant conidia required 10 h longer to germinate 50% at optimal 25 degrees C than wild-type conidia. Intriguingly, cultivation of the mutant conidia in a trehalose-peptone broth mimic to insect hemolymph resulted in 83% reduction in blastospore yield but only slight decrease in biomass level, indicating severe defects in transition of hyphae to blastospores. LT50 for the deletion mutant against Galleria mellonella larvae through normal cuticle infection was prolonged to 7.4 d from a wild-type estimate of 4.7 d. During colony growth, additionally, the deletion mutant displayed hypersensitivity to Congo red, menadione, H2O2 and heat shock but increased tolerance to cyclosporine A and rapamycin. All of changes were restored by targeted gene complementation. Altogether, CypB takes part in sustaining normal growth, aerial conidiation, conidial germination, dimorphic transition, stress tolerance and pathogenicity in B. bassiana.