蛋白激酶Cla4对黄曲霉生长发育、毒素合成和致病力的影响

黄曲霉Aspergillus flavus是机会性的动物和植物致病性丝状真菌,保守的PAK(p21-activated protein kinases)样蛋白激酶对信号传导、细胞周期进程和细胞形态发生具有重要作用.通过同源重组方法构建敲除突变株(ΔAflcla4),研究Aflcla4基因对黄曲霉营养生长、分生孢子产生、...

Protein kinase Cla4 regulates morphology development,aflatoxin biosynthesis and pathogenicity of Aspergillus flavus

Aspergillus flavus is an opportunistic pathogenic filamentous fungus that can influence plant and animals.The conservative Cla4 PAK(p21-activated protein kinases)protein kinase is important for signal transmission,cell cycle progression and morphogenesis.A homologous recombination method was used to construct a knockout mutant strain(ΔAflcla4)for revealing the biological functions of Aflcla4 gene performing vegetative growth,spore production,sclerotial formation,aflatoxin production,stress response and pathogenicity of A.flavus.Compared with the wild type strain,mycelium growth rate of the knockout mutantΔAflcla4 was significantly decreased,the mycelium was irregularly bifurcated,conidial production was significantly reduced,and the color became transparent.TheΔAflcla4 mutant displayed increase in sensitivity to cell wall integrity and osmotic stresses.It was found that the pathogenicity ofΔAflcla4 to peanut and corn seeds became impaired,and the ability to produce toxins was also dramatically declined.The deletion of Aflcla4 resulted in the defect of sclerotial formation,causing decrease of ability to deal with adverse environmental changes.PAK kinase Cla4 plays critical roles in development,aflatoxin production,and sclerotial formation by regulating related genes expression in A.flavus.