Whole genome sequencing of the oomycete pathogen Sclerospora graminicola and prediction of effector candidates
M. KOBAYASHI (1), Y. Hiraka (2), A. Abe (2), H. Yaegashi (2), S. Natsume (2), H. Kikuchi (2), H. Takagi (2), H. Saitoh (2), J. Win (3), S. Kamoun (3), R. Terauchi (2) (1) Iwate Biotechnology Research Center, Japan; (2) Iwate Biotechnology Research Center, Japan; (3) The Sainsbury Laboratory, United Kingdom

Downy mildew, caused by the oomycete Sclerospora graminicola, is an economically important disease of foxtail millet (Setaria italica). Plants infected with S. graminicola are generally stunted and do not produce panicles, resulting in a serious yield loss. Sclerospora species and its close relative Peronosclerospora species cause phyllody symptoms in their hosts, with abnormal development of floral parts into leafy structure. To search for virulence effectors of S. graminicola responsible for the host phyllody, we carried out whole genome sequencing of the species by Illumina sequencer and performed de novo assembly of the 360 Mb genome. Seventy-three percent of the genome was composed of repetitive elements and 16,736 genes were predicted in the genome with the support of RNA-seq data. The predicted genes included those for effector-like proteins shoeing high sequence similarity to the previously identified effectors in other pathogenic oomycetes. In addition, jacalin-like lectin domain-containing secreted protein genes were enriched in S. graminicola as compared to other oomycetes.  We found 305 out of 1,220 putative secreted protein genes were upregulated in infected plant tissues compared to sporangia and zoospores. To identify the effectors involved in phyllody, we are overexpressing selected effector candidate genes in rice.

Abstract Number: P11-368
Session Type: Poster