不同波长光源对新蚜虫疠霉产孢能力的影响及霉菌蓝光受体基因的克隆和表达分析

Effects of different wavelength light on the sporulation ability of Pandora neoaphidis and the cloning and expression analysis of fungal blue-light receptor gene

光在调控真菌的多种生理过程中发挥着重要作用。为探究光照对新蚜虫疠霉Pandora neoaphidis产孢的影响,本文研究了不同波长光源(蓝光、绿光、白光、红光、黄光)和无光黑暗条件对新蚜虫疠霉分生孢子弹射能力的影响,通过cDNA末端的快速扩增(RACE)对新蚜虫疠霉的蓝光受体蛋白基因pnwc-1进行克隆并对其进行生物信息学分析,利用qRT-PCR对蓝光光源不同照射时长下pnwc-1的表达量进行了定量分析。结果表明,蓝色光源(波长460–465nm)照射后的新蚜虫疠霉菌丝产生的分生孢子数量显著高于其他波长光源,排序为:蓝光>绿光>白光>红光>黄光>无光。另外,分析克隆获得的全长为2 423bp的pnwc-1基因发现,其编码的蛋白具有蓝光受体蛋白典型的保守结构域,同源比对结果显示新蚜虫疠霉与接合菌门真菌归为一类但相对独立。qRT-PCR的定量分析结果表明随着照射时长增加,蓝光处理能显著提高pnwc-1的表达量,而且pnwc-1的相对表达量与累积产孢量存在正相关(R2=0.9798)。本研究为后续蓝光及其受体基因功能的深入研究提供了实验基础,并促进以新蚜虫疠霉为代表的虫霉目真菌在害虫生物防治中的应用。

Light plays an important role in regulating various physiological processes of fungi. In order to investigate the influence of light irradiation on the sporulation of Pandora neoaphidis F98028, the effect of different wavelength light on discharging conidia of P. neoaphidis were studied. Based on transcriptome information, the white collar protein gene pnwc-1 encoding a putative blue-light receptor protein was cloned and analyzed by bioinformatics. The expression of pnwc-1 during different blue light irradiation period were quantified by qRT-PCR. Results showed that the blue light(wavelength 460–465 nm) could significantly stimulate the sporulation of P. neoaphidis. The sporulation ability affected by different irradiation could be sorted as blue light > green light > white light > red light > yellow light > dark. The full-length of cloned pnwc-1 gene was 2 423 bp and the gene was found to encode a protein with a conserved domain which was typical of the blue-light receptor protein. Homologous alignment suggested that P. neoaphidis was close to zygomycete fungi but had a relatively independent branch in phylogenetic relationship. The quantitative analysis of qRT-PCR demonstrated that the treatment with increasing irradiation duration of blue light could significantly enhance the expression of pnwc-1, and the relative expression of pnwc-1 was positively correlated with the cumulative sporulation(R2=0.9798). Conclusively, this study provides a basis for further research on the function of blue light and blue-light receptor gene of P. neoaphidis, enforcing the application of the fungi in the biological control.