Enhanced Expression of Thaumatin-like Protein Gene (LeTLP1) Endows Resistance to Trichoderma atroviride in Lentinula edodes.

Lentinula edodes (shiitake mushrooms) is heavily affected by the infection of Trichoderma atroviride, causing yield loss and decreases quality in shiitake mushrooms. The selection and breeding of fungal-resistant L. edodes species are an important approach to protecting L. edodes from T. atroviride infection. Herein, a highly resistant L. edodes strain (Y3334) and a susceptible strain (Y55) were obtained by using a resistance evaluation test. Transcriptome analyses and qRT-PCR detection showed that the expression level of LeTLP1 (LE01Gene05009) was strongly induced in response to T. atroviride infection in the resistant Y3334. Then, LeTLP1-silenced and LeTLP1-overexpression transformants were obtained. Overexpression of LeTLP1 resulted in resistance to T. atroviride. Compared with the parent strain Y3334, LeTLP1-silenced transformants had reduced resistance relative to T. atroviride. Additionally, the LeTLP1 protein (Y3334) exhibited significant antifungal activity against T. atroviride. These findings suggest that overexpression of LeTLP1 is a major mechanism for the resistance of L. edodes to T. atroviride. The molecular basis provides a theoretical basis for the breeding of resistant L. edodes strains and can eventually contribute to the mushroom cultivation industry and human health.