Regulation of dikaryon-expressed genes by FRT1 in the basidiomycete Schizophyllum commune

• Published in: Fungal genetics and biology Vol. 26; no. 1; pp. 33 - 47
• Main Authors: Horton, J.S, Palmer, G.E, Smith, W.J
• Format: Journal Article
• Language: English
• Published: United States 01-02-1999
• Subjects: aerial growth; Alleles; Animals; Autoantigens - genetics; biological development; Blotting, Northern; Carrier Proteins - genetics; frt1 gene; fruit bodies; fungal anatomy; Fungal Proteins; gene expression; Gene Expression - genetics; genes; Genes, Fungal - genetics; genetic regulation; growth; hydrophobins; light; mating behavior; messenger RNA; Microscopy, Electron, Scanning; mutants; mycelium; proteins; Reverse Transcriptase Polymerase Chain Reaction; Ribonucleoproteins, Small Nuclear; Schizophyllum - genetics; Schizophyllum - physiology; Schizophyllum commune; sexual reproduction; snRNP Core Proteins; Transgenes - genetics; Viral Proteins - genetics
• ISSN: 1087-1845; 1096-0937
• DOI: 10.1006/fgbi.1998.1104

The gene FRT1 has previously been shown to induce homokaryotic fruiting in transformation recipients of the basidiomycete Schizophyllum commune. In this paper, we demonstrate by gene disruption experiments that FRT1 is dispensable for dikaryotic fruiting. Nonfruiting homokaryotic FRT1 disruptant strains exhibited enhanced aerial growth of mycelia compared to wild type. Introduction of a functional FRT1 allele into the disruptant restored the wild-type colony morphology. Transcript abundance of the dikaryon-expressed SC1 and SC4 hydrophobin genes and the SC7 gene were greatly elevated in homokaryotic FRT1 disruptant strains. Growth of the disruptant strains under continuous light was found to inhibit the elevation of SC1 and SC4 transcript levels, but not of SC7 mRNA. These data suggest that the role of FRT1 in vegetatively growing homokaryons is to act as a negative regulator of dikaryon-expressed genes.