RNA干扰Fus3基因对二态性真菌马尔尼菲青霉菌的孢子形成和细胞壁组分合成功能的影响

Effects of Fus3 RNAi on sporulation and cell wall composition synthesis in the dimorphic fungus Penicillium marneffei

马尔尼菲青霉菌Penicillium marneffei是一种重要的条件致病真菌,可致艾滋病患者产生严重的系统性霉菌病并发症。基因组学的研究和RNA干扰技术,为马尔尼菲青霉菌致病基因和致病机制的深入探讨提供了可能。我们研究马尔尼菲青霉菌的一个新基因Fus3,它是丝氨酸/苏氨酸-特异性激酶丝裂原活化蛋白激酶家族的成员。为了研究Fus3的功能,我们利用根癌农杆菌介导的双链RNA干扰技术构建了Fus3 RNA干扰菌株(Fus3-i)。RNA干扰的活性是由木糖诱导的启动子xylP控制的。Fus3基因活性下降后影响了马尔尼菲青霉菌生长,包括孢子的生成,细胞壁组分的合成。实验表明,Fus3基因对于马尔尼菲青霉菌细胞生长发育起着重要的调控作用,为研究真菌疾病提供了帮助。

Penicillium marneffei is an important opportunistic pathogenic fungus causing a fatal systemic mycosis in patients infected with human immunodeficiency virus （HIV）. Based on the genomic work and RNA interference, candidate virulence associated genes and virulence mechanisms are investigated to make it possible for overcoming the Penicillium marneffei infection. We characterized a novel Penicillium marneffei Fus3 gene, which is a member of the mitogen-activated protein kinase （MAPK） family of serine/threonine-specific kinases. To study biological function of Fus3, we constructed a Fus3 gene RNA interference strain （Fus3-i） using dsRNAi mediated by Agrobacterium tumefaciens. The activity of RNA interference is under control of promoter xylP, which can be induced by xylose. The reduction of Fus3 activity displays morphogenesis changes including the change of sporogenesis and cell-wall synthesis. We propose that Fus3 gene might be involved in regulation of cell integrity, and therefore these findings might contribute to study of treating fungal diseases.