Cloning and characterisation of a chitin synthase gene cDNA from the cultivated mushroom Agaricus bisporus and its expression during morphogenesis.

Full-length cDNA of a chitin synthase gene (chs1) was cloned from Agaricus bisporus by screening a cDNA library with a PCR amplified fragment of the chitin synthase gene. The chs1 contains an open reading frame of 2727 bp encoding a polypeptide of 909 amino acids and deduced molecular mass 102.3 kDa and pI 8.23. The central region of chs1 showed strong homology to other fungal chitin synthase genes with seven conserved domains. It belongs to the chitin synthase class III, analogous to chsB from Aspergillus nidulans, chsC and chsG from A. fumigatus and chs-1 from Neurospora crassa. It appears to be fruit body induced as the transcripts were higher in the developing mushroom compared to any mycelial stage.