Evaluating the effects of blue and red light on the stress tolerance and the proteome of the entomopathogenic fungus Metarhizium acridum

Abstract

Light response is a wide studied phenomenon in some fungi, such as Neurospora crassa and Aspergillus nidulans. However, the vast majority of fungal species have not had their light response mechanism elucidated. In the entomopathogenic fungus Metarhizium acridum, light is responsible for inducing an increase in tolerance to UV-B (290-315 nm) radiation. Given the potential use of this fungus for the biological control of insects, this increased tolerance is a high-valued characteristic, as one of the most important limitations of using fungi in biological control is inactivation due to solar radiation, particularly ultraviolet radiation. Even though induction of UV-B tolerance is a known effect of light in M. acridum, the molecular mechanism resulting in this increased tolerance has not been determined. Therefore, a proteomic approach combined to obtaining mutants for the main photoreceptors should provide knowledge for a better understanding of light responses in this fungus. We hope that the results gathered here will provide good information for a mechanistic evaluation of light responses and could also be used for producing strains with increased tolerance to UV-B radiation to be employed in biological control.