EXPRESSION OF 2 CLOSELY LINKED HYDROPHOBIN GENES OF COPRINUS-CINEREUSIS MONOKARYON-SPECIFIC AND DOWN-REGULATED BY THE OID-1 MUTATION

A protein with characteristic properties of a fungal hydrophobin (CoH1 ) was isolated from the monokaryotic stage of the basidiomycete Coprin us cinereus, A cosmid clone containing the corresponding gene (coH1) w as identified using a cDNA probe derived by RT-PCR. Hybridization and sequence analysis identified a second gene, coH2, just 4.1 kb downstre am of coH1 encoding a hydrophobin (CoH2) with 64% sequence identity, B oth coH1 and coH2 are subject to developmental regulation. They are ex pressed in vegetative monokaryotic cells but not in the asexual oidia produced on the surface of monokaryons. Transcripts of the genes were barely detected in dikaryotic mycelium and were absent from fruit bodi es, Loss of aerial growth due to a mutation known as oid-1 was correla ted with lack of both hydrophobins. (C) 1997 Academic Press.