Abstract

The orthologous gene to histidine kinase SLN1 of Saccharomyces cerevisiae was found in the Candida glabrata genome database; we performed both in silico and molecular analyses of this gene. A phylogenetic analysis confirmed the close relatedness between these orthologous genes. We found that C. glabrata Sln1p presents two functional domains: a histidine kinase domain, and a response regulator domain, both similar to S. cerevisiae. Eight possible nitrogen source-activated transcription-factor binding sites and one for Mns4p/Mns2p were found. Expression analyses by semi-quantitative RT-PCR revealed that this gene was down-regulated when the yeast was cultured under osmotic and oxidative stress conditions, different nitrogen sources and acidic pH; but in alkaline pH, the expression of the SLN1 gene was recovered after 6 h. Hence, our results suggested that the SLN1 gene is involved in adaptation to different environmental stress conditions, similarly to the orthologous genes present in S. cerevisiae and Candida albicans

Key words: Candida glabrata, histidine-kinase Sln1p, osmotic and oxidative stress