, an C2H2 transcription factor from , positively regulates mycelium response to osmotic stress.

is an edible and medicinal mushroom with the capacity to produce sclerotia. However, the mechanism of sclerotia formation is unclear. CRZ1 is a C2H2 family transcription factor involved in the Ca-calcineurin signaling pathway, which has the function of regulating sclerotia formation, maintaining ion homeostasis, and responding to stress. In this study, we identified 28 C2H2 transcription factors in genome, 13 of which are differentially expressed between mycelium and sclerotia, including . Combining DNA affinity purification and sequencing (DAP-seq) and quantitative real-time PCR (qRT-PCR), three genes (, , ) were identified as putative target genes containing a putative binding motif (GTGGCG) within their promoter. Yeast single hybridization (Y1H) and EMSA further confirmed that can bind to the promoter region of , , and . PuCRZ1 gene could reduce the sensitivity of NaCl in yeast cells. Furthermore, overexpression of the PuCRZ1 target gene, especially the FVLY domain containing gene , could improve the mycelia growth rate and mannitol tolerance in . These results demonstrate that in the Ca-calcineurin signaling pathway plays an important role in mycelia growth, as well as osmotic stress tolerance.