Differentially expressed genes under simulated microgravity in fruiting bodies of the fungus Pleurotus ostreatus.

In response to a change in the direction of gravity, morphogenetic changes of fruiting bodies of fungi are usually observed as gravitropism. Although gravitropism in higher fungi has been studied for over 100 years, there is no convincing evidence regarding the graviperception mechanism in mushrooms. To understand gravitropism in mushrooms, we isolated differentially expressed genes in Pleurotus ostreatus (oyster mushroom) fruiting bodies developed under three-dimensional clinostat-simulated microgravity. Subtractive hybridization, cDNA representational difference analysis was used for gene analysis and resulted in the isolation of 36 individual genes (17 upregulated and 19 downregulated) under clinorotation. The phenotype of fruiting bodies developed under simulated microgravity vividly depicted the gravitropism in mushrooms. Our results suggest that the differentially expressed genes responding to gravitational change are involved in several potential cellular mechanisms during fruiting body formation of P. ostreatus.