Objectives: To elucidate the mechanism of cellulase signal transduction in filamentous fungi including the components of the cellulase induction pathway.
Results: Neurospora crassa ncw-1 encodes a non-anchored cell wall protein. The absence of ncw-1 increased cellulase gene expression and this is not due to relieving carbon catabolite repression mediated by the cre-1 pathway. A mutant lacking genes encoding both three major β-glucosidase enzymes and NCW-1 (Δ3βGΔncw-1) was constructed. Transcriptome analysis of the quadruple mutant demonstrated enhanced expression of cellodextrin transporters after ncw-1 deletion, indicating that ncw-1 affects cellulase expression and production by inhibiting the uptake of the cellodextrin.
Conclusions: NCW-1 is a novel component that plays a critical role in the cellulase induction signaling pathway.
Keywords: Cell wall protein; Cellobiose uptake; Cellodextrin transporter; Cellulase induction; Neurospora crassa.