The Effect of Variable CO۲ Concentrations on HSP۷۰ Gene in Trichophyton Rubrum and Microsporeum Canis

Background and Objectivs: Trichophyton rubrum is considered as the most common causes of dermatophytosis in human skin and nail tissues. Microsporeum canis is a zoophile dermatophyte which can be transmited to human. HSP۷۰ is a ۷۰ KD heat shock protein in fungi. In this study, the effects of variable CO۲ concentrations were examined on HSP۷۰ expression in T. rubrum and M. canis. Materials and Methods: Strains used in this study were obtained from skin scales and nails of the patients who were suffering from onychomycosis. Samples were cultured on Sabouraud dextrose broth (SDB) and incubated at ۲۵°C for ۲, ۴ and ۷ days under ۳%, ۵%, and ۱۰% of CO۲ concentrations. Control cultures maintained for ۷ days without CO۲ concentrations. Then, RNA was isolated from the harvested mycelia mass, and HSP۷۰ gene expression was studied in T. rubrum and M. canis by RT-PCR. The obtained results were compared to the Beta actin as a house keeping gene. Results: The results of this study revealed the maximum variations under ۳%,۵%, and ۱۰% of CO۲ concentrations in maximum ۷ days incubation period, and the expression of HSP۷۰ gene showed different  variations  under different CO۲ concentrations. Conclusion: Our results showed a negative effect of CO۲ concentrations in the expression of HSP۷۰ in T. Rubrum and a positive effect in M. canis comparing to the controls.

Keywords:

Dermatophyte , Trichophyton rubrum , Microsporeum canis , HSP۷۰ Gene