Sequence Analysis and Expression of a Blue-Light Photoreceptor Gene, Le.phrA from the Basidiomycetous Mushroom Lentinula edodes

Abstract

We cloned and sequenced a photoreceptor gene (Le.phrA) from the basidiomycete Lentinula edodes. The product of Le.phrA, Le.PHRA (924 aa residues) contained a serine-rich region, an LOV domain and two PAS domains. It was clearly smaller than other fungal LOV domain-containing blue-light photoreceptors such as Coprinopsis cinerea Dst1 (1,175 aa), Neurospora crassa WC-1 (1,167 aa), and Cryptococcus neoformans WC-1 (1,141 aa). The Le.phrA gene was found to be transcribed at all stages of the fruiting-body formation of L. edodes, but it was most abundantly transcribed in the immature fruiting body. Fully-matured fruiting body also contained relatively large amounts of Le.phrA transcript. Although the transcript level was lower, preprimordial aggregated mycelial cells grown under a light environment contained larger amounts of the transcript than those grown under continuous darkness, suggesting a light-enhanced expression of the Le.phrA gene. Hymenophore-depleted pileus contained a markedly higher level of the transcript than the stipe.