Analysis of expressed sequence tags from the ectomycorrhizal basidiomycetes Laccaria bicolor and Pisolithus microcarpus

Abstract

Summary• In an effort to discover genes that are expressed in the ectomycorrhizal basidiomycetes Laccaria bicolor and Pisolithus microcarpus , and in P. microcarpus/ Eucalyptus globulus ectomycorrhizas, we have sequenced 1519 and 1681 expressed sequence tags (ESTs) from L. bicolor and P. microcarpus cDNA libraries.• Contig analysis resulted in 905 and 806 tentative consensus sequences (unique transcripts) in L. bicolor and P. microcarpus , respectively. For 36% of the ESTs, significant similarities to sequences in databases were detected. The most abundant transcripts showed no similarity to previously identified genes. Sequence redundancy analysis between different developmental stages indicated that several genes were differentially expressed in free-living mycelium and symbiotic tissues of P. microcarpus.• Based on sequence similarity, 11% of L. bicolor unique transcripts were also detected in P. microcarpus . Similarly, L. bicolor and P. microcarpus shared only a low proportion of common transcripts with other basidiomycetous fungi, such as Pleurotus ostreatus and Agaricus bisporus. Such a low proportion of shared transcripts between basidiomycetes suggests, on the one hand, that the variability of expressed transcripts in different fungi and fungal tissues is considerably high. On the other hand, it might reflect the low number of GenBank entries of basidiomycetous origin and stresses the necessity of an additional sequencing effort.• The present ESTs provide a valuable resource for future research on the development and functioning of ectomycorrhizas.

Mitogen-Activated Protein Kinase Signaling in Plant-Interacting Fungi: Distinct Messages from Conserved Messengers

“…The development of long-lasting compatible interactions between mutualistic telluric fungi and the roots of forest trees requires highly controlled reprogramming of cellular activities, and consistent with this, signaling genes are overrepresented in collections of ESTs isolated from symbiotically associated partners Sundaram et al, 2001;Voiblet et al, 2001;Peter et al, 2003). Earlier attempts to investigate gene expression during mycorrhiza development reported the presence of MAPKs expressed in the free-living mycelium of the basidiomycetes Pisolithus microcarpus and L. bicolor (Peter et al, 2003) and the induction of several signaling-related transcripts, including those encoding MAPKs, during mycorrhiza development Duplessis et al, 2005;Le Quéré et al, 2005).…”

“…Earlier attempts to investigate gene expression during mycorrhiza development reported the presence of MAPKs expressed in the free-living mycelium of the basidiomycetes Pisolithus microcarpus and L. bicolor (Peter et al, 2003) and the induction of several signaling-related transcripts, including those encoding MAPKs, during mycorrhiza development Duplessis et al, 2005;Le Quéré et al, 2005). The recent availability of genome sequences from ectomycorrhizal fungi (L. bicolor and Tuber melanosporum) has now made it possible to identify the full complement of MAPK signaling components in plant-beneficial fungi (Martin et al, 2008(Martin et al, , 2010.…”

A Signaling-Regulated, Short-Chain Dehydrogenase of Stagonospora nodorum Regulates Asexual Development

“…SNOG_11081 encodes a putative concanamycin-induced protein C. CipC was first identified as an accumulated protein in Aspergillus nidulans exposed to the antibiotic concanamycin A (36). Orthologues of CipC were also identified in other fungi; however, their function is unknown (2, 29, 37,43,64). The gene expression profile of CipC in planta showed maximal transcript abundance 1 day postinfection, which suggests that this gene may play a role during early infection.…”

Identification of Genes Differentially Expressed in Extraradical Mycelium and Ectomycorrhizal Roots during Paxillus involutus-Betula pendula Ectomycorrhizal Symbiosis

“…We may therefore speculate that the up-regulation of cipC may be linked to changes in the growth morphology of the fungus. Interestingly, cipC homologues have also been found in several EST studies of ECM fungi, including Laccaria laccata and P. tinctorius (38).…”