Submitted to: Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/20/2004
Publication Date: 3/1/2005
Citation: Lin, K.C., Bushnell, W.R., Szabo, L.J. 2005. Molecular characterization of the ribosomal protein L25 from the stem rust fungus. Plant Pathology Bulletin. 13:251-260. Interpretive Summary: Stem rust has a long history of causing major damage to small cereal grain (wheat, oat, and barley) production in North America. Disease losses have been greatly reduced by the introduction of cultivars with stem rust resistance genes and the eradication of the alternative host in the central Great Plains. However, in order to continue effective control of the wheat stem rust pathogen, we need to understand the basic mechanisms by which this pathogen causes disease. Molecular genetics provides powerful tools to elucidate the genes involved. As one step to providing these tools, we have cloned a highly expressed gene that will be used by scientists for developing vectors to transfer DNA into rust fungi and DNA markers.
Technical Abstract: A cDNA clone (pCRL130) encoding a 25S rRNA-binding protein (L25), was isolated from the oat stem rust fungus, Puccinia graminis f.sp. avenae. The cDNA clone contains a 660 bp insert that encodes a putative polypeptide of 158 amino acids and shows 66-82% similarity to those of eukaryotic ribosomal L25 proteins. Transcripts of P. graminis Rpl25 (L25 gene) were detected as early as 48 h after host plants were inoculated with the fungus; temporal patterns of transcript accumulation were closely correlated with fungal growth in host plants. Phylogenetic analysis of L23/L25 proteins showed that P. graminis L25 was similar to other fungal L25 proteins but was not closely related to them. This is the first reported clone of an L25 protein from a filamentous fungus or from a Basidiomycete.