Lighting Conditions Influence the Dynamics of Protease Synthesis and Proteasomal Activity in the White Rot Fungus Cerrena unicolor

Abstract

Recent transcriptomic and biochemical studies have revealed that light influences the global gene expression profile and metabolism of the white-rot fungus Cerrena unicolor. Here, we aimed to reveal the involvement of proteases and ubiquitin-mediated proteolysis by the 26S proteasome in the response of this fungus to white, red, blue and green lighting conditions and darkness. The changes in the expression profile of C. unicolor genes putatively engaged in proteolysis were found to be unique and specific to the applied wavelength of light. It was also demonstrated that the activity of proteases in the culture fluid and mycelium measured using natural and synthetic substrates was regulated by light and was substrate-dependent. A clear influence of light on protein turnover and the qualitative and quantitative changes in the hydrolytic degradation of proteins catalyzed by various types of proteases was shown. The analysis of activity associated with the 26S proteasome showed a key role of ATP-dependent proteolysis in the initial stages of adaptation of fungal cells to the stress factors. It was suggested that the light-sensing pathways in C. unicolor are cross-linked with stress signaling and secretion of proteases presumably serving as regulatory molecules.

Comparative Proteomic Analysis Reveals Candidate Pathways Related to the Effect of Different Light Qualities on the Development of Mycelium and Fruiting Body of Pleurotus ostreatus

“…Environmental factors such as nutrients, temperature, carbon dioxide concentration, and light are crucial for the growth of mushroom-forming fungi. − Specifically, light plays a significant role in regulating the growth, development, and metabolism of mushrooms as an environment signal, and factors such as light intensity and wavelength are particularly important. − Therefore, providing proper light conditions is essential for the induction and development of fruiting bodies. The effect of light has been investigated in various mushrooms, including Coprinopsis cinerea, Inonotus rheades, Lentinula edodes, − Pleurotus ostreatus, , Pleurotus eryngii, − Cerrena unicolor, − and Hypsizygus marmoreus. , Studies have shown that different light qualities have varying effects on the growth of mycelium and the development of primordia or fruiting bodies . For example, although most mushrooms do not require light during the mycelial growth stage, the mycelia of Cordyceps militaris exposed to white light exhibit significantly faster growth compared to those kept in the dark.…”