探討剔除白色念珠菌 ORF19.6586 及 RHD3 之型態變化及藥物敏感性之影響

Abstract

白色念珠菌為一種存在於人體中共生的伺機性病原菌。目前研究已知白色念珠菌的型態轉變的能力和致病力是有相關性，而在實驗室前人利用基因表現比對 (gene profiling) 篩選出受 transcription factor Cph1p 及 Efg1p 調控之下游基因 CaORF19.6586 及 CaRHD3，利用 SAT1 flipper cassette 進行同源重組方式置換目標基因，並將單套基因重新置入雙套基因剔除株進行基因補救，接著跟前人構築之 GRE2、ORF19.173、ORF19.7310的突變株一起分析其形態及藥物的感受性。結果顯示雖然各基因突變株在型態變化上與其 parental strain 沒有差異，但在藥物感受性與其 parental strain 相比皆是呈現較為不敏感的表現，因此這些基因的活性與藥物感受性相關。

The opportunistic fungus Candida albicans is commensal in human. The ability of Candida albicans to switch between yeast and hyphal forms is implicated in its pathogenicity. Previous study shows that CaORF19.6586 and CaRHD3, selected by gene profiling are regulated by transcription factors Cph1p and Efg1p. First, I used SAT1 flipper cassette system to construct homologous recombination to displace target genes CaORF19.6586 and CaRHD3, and then reinserted a single wild-type allele into the homozygous knock-out strain to construct rescued strains. Together with the constructed stains for CaGRE2, CaORF19.173 and CaORF19.7310, I then analyzed the mutation effects on morphogenesis and drug susceptibilities. The results indicated that there were no different on morphogenesis but the knockout mutants were less susceptible to drugs. So the activity of these genes is related to drug susceptibility.