Expression Profile of Laccase Gene Family in White-Rot Basidiomycete under Different Environmental Stresses.

Laccases belong to ligninolytic enzymes and play important roles in various biological processes of filamentous fungi, including fruiting-body formation and lignin degradation. The process of fruiting-body development in is complex and is greatly affected by environmental conditions. In this paper, 14 multicopper oxidase-encoding (laccase) genes were analyzed in the draft genome sequence of strain W1-26, followed by a search of multiple stress-related -elements in the promoter region of these laccase genes, and then a transcription profile analysis of 14 laccase genes () under the conditions of different carbon sources, temperatures, and photoperiods. All laccase genes were significantly regulated by varying carbon source materials. The expression of only two laccase genes ( and ) was induced by sodium-lignosulphonate and the expression of most laccase genes was specifically upregulated in glucose medium. Under different temperature conditions, the expression levels of most laccase genes decreased at 39 °C and transcription was significantly increased for , , , , , , and after induction for 24 h at 10 °C, indicating their involvement in primordium differentiation. Tyrosinase, which is involved in melanin synthesis, was clustered with the same group as and in all the different photoperiod treatments. Meanwhile, five laccase genes (, , , , and ) showed similar expression profiles to that of two blue light receptor genes ( and ) in the 12 h light/12 h dark treatment, suggesting the involvement of laccase genes in the adaptation process of to the changing environment and fruiting-body formation. This study contributes to our understanding of the function of the different genes and facilitates the screening of key genes from the laccase gene family for further functional research.