[Effect of CCH1 and MID1 in calcium influx under alkaline pH and its regulation by Crz1p transcription factor in Candida albicans].
In Candida albicans, adaptation to environmental pH is relevant to its pathogenicity. Calcium signaling pathway involves in many stress responses and often accompany with Ca2+ fluctuation. We constructed CCH1 and MID1 mutant strains and studied their effect on calcium influx and further investigated the regulation by Crz1p transcription factor. We used PCR-directed gene disruption to construct cch1delta/delta and mid1delta/delta null mutant. By using a flow cytometry-based method we monitored the free cytosolic Ca2+ levels under alkaline stress. Moreover, we constructed pPHO89-LacZ plasmids and by beta-Galactosidase assays, we analyzed the changes of LacZ activities after gene disruption. The results showed that alkaline stress induced calcium burst reduced obviously in cch1delta/delta and mid1delta/delta mutant strains, also for LacZ activities, and fully abolished in crz1delta/delta mutant strain. Finally, by realtime PCR, we confirmed the regulation role of Crz1p in CCH1 and MID1 genes but in a calcineurin independent way. Studies on the effect of calcium pathway on response to alkaline stress will provide an important theoretical basis for Candida albicans infection-oriented treatment and new drug targets.
Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, Nankai University, Tianjin 300071, China.
Hui
H
Wang
Ning
N
Xu
Laijun
L
Xing
Mingchun
M
Li
Dongsheng
D
Wei
D015220:Calcium Channels / Q000378:metabolism*; D002176:Candida albicans / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D005656:Fungal Proteins / Q000235:genetics / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal; D006863:Hydrogen-Ion Concentration; D015398:Signal Transduction; D013312:Stress, Physiological; D014157:Transcription Factors / Q000378:metabolism / Q000502:physiology*
D015220:Calcium Channels; D005656:Fungal Proteins; D014157:Transcription Factors