Genetic regulation of compost and plant degradation in Agaricus bisporus

Agaricus bisporus, the common button mushroom, is a major contributor to the global carbon-nitrogen cycle through its role as a secondary decomposer of plant and leaf litter. It is also an economically significant mushroom with a domestic farm gate value in excess of €120 million. This research aims to elucidate the molecular mechanisms involved in compost and plant matter degradation by A. bisporus. An examination of the entire genome using microarray analysis was carried out on A. bisporusat 48 h intervals over the course of its commercial lifecycle. This data revealed several genes that appear to be involved in the genetic regulation of mushroom production. From this data, genes with potentially critical roles in compost utilisation and plant matter degradation were identified. Five genes of significant interest were selected for further study. These include three carbohydrate degrading genes and an unknown gene which appears to be unique to A. bisporus, all of which had an expression profile that matched the commercial growth pattern. The fifth gene was selected based on its significant down-regulation during peak mushroom growth. To further compliment this data a bioinformatic analysis of known transcription factor binding sites present within each promoter of A. bisporus is also being carried out. The data generated from this study will provide crucial insight into the mechanisms behind the regulation of A. bisporus growth and its ability to degrade plant matter and compost degradation.