The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent stra...The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies.展开更多
Wall-associated kinases(WAKs) play an important role in plant defense and development.Considerable progress has been made in understanding WAK genes in Arabidopsis thaliana.However, much less is known about these gene...Wall-associated kinases(WAKs) play an important role in plant defense and development.Considerable progress has been made in understanding WAK genes in Arabidopsis thaliana.However, much less is known about these genes in common wheat. Here, we isolated a novel wheat WAK gene TaWAK5 from sharp eyespot disease-resistant wheat line CI12633,based on a differentially-expressed sequence identified by microarray analysis. The transcript abundance of TaWAK5 was rapidly increased following inoculation with the pathogen Rhizoctonia cerealis. TaWAK5 in resistant wheat lines was induced to higher levels than in susceptible lines at 7 days post inoculation with R. cerealis. The expression of TaWAK5 was also induced by treatments with exogenous salicylic acid, abscisic acid, and methyl jasmonate. The deduced TaWAK5 protein contained a signal peptide, two epidermal growth factor(EGF)-like repeats, a transmembrane domain, and a serine/threonine protein kinase catalytic domain. Subcellular localization analyses in onion epidermal cells indicated that the TaWAK5 protein was localized to the plasma membrane. Virus-induced gene silencing of TaWAK5 in CI12633 plants showed that the silencing of TaWAK5 did not obviously impair wheat resistance to R. cerealis, suggesting that TaWAK5 may be not the major gene in wheat defense response to R. cerealis, or that it is functionally redundant with other genes. This study paves the way for further research into WAK functions in wheat stress physiology.展开更多
基金funded by the National Key Project for Research on Transgenic Biology,China(2016ZX08002001 to Zengyan Zhang)。
文摘The necrotrophic fungus Rhizoctonia cerealis is the causal agent of devastating diseases of cereal crops including wheat(Triticum aestivum).We present a high-quality genome assembly of R.cerealis Rc207,a virulent strain causing wheat sharp eyespot.The assembly(56.36 Mb)is composed of 17.87%repeat sequences and 14,433 predicted protein-encoding genes.The Rc207 genome encodes a large and diverse set of genes involved in pathogenicity,especially rich in those encoding secreted proteins,carbohydrateactive enzymes(CAZymes),peptidases,nucleases,cytochrome P450,and secondary metabolismassociated enzymes.Most secretory protein-encoding genes,including CAZymes,peroxygenases,dehydrogenases,and cytochrome P450,were up-regulated during fungal infection of wheat.We identified 831 candidate secretory effectors and validated the functions of 10 up-regulated candidate effector proteins.Of them,nine were confirmed as necrotrophic pathogen’s effectors promoting fungal infection.Abundant potential mobile or plastic genomic regions rich in repeat sequences suggest their roles in fungal adaption and virulence-associated genomic evolution.This study provides valuable resources for further comparative and functional genomics on important fungal pathogens,and provides essential tools for development of effective disease control strategies.
基金funded by the National Natural Science Foundation of China(31271799)the National "Key Sci-Tech" program,China(2013ZX08002-001-004)the China–Czech Government Science and Technology Cooperation Project(40–3 and LH12196)
文摘Wall-associated kinases(WAKs) play an important role in plant defense and development.Considerable progress has been made in understanding WAK genes in Arabidopsis thaliana.However, much less is known about these genes in common wheat. Here, we isolated a novel wheat WAK gene TaWAK5 from sharp eyespot disease-resistant wheat line CI12633,based on a differentially-expressed sequence identified by microarray analysis. The transcript abundance of TaWAK5 was rapidly increased following inoculation with the pathogen Rhizoctonia cerealis. TaWAK5 in resistant wheat lines was induced to higher levels than in susceptible lines at 7 days post inoculation with R. cerealis. The expression of TaWAK5 was also induced by treatments with exogenous salicylic acid, abscisic acid, and methyl jasmonate. The deduced TaWAK5 protein contained a signal peptide, two epidermal growth factor(EGF)-like repeats, a transmembrane domain, and a serine/threonine protein kinase catalytic domain. Subcellular localization analyses in onion epidermal cells indicated that the TaWAK5 protein was localized to the plasma membrane. Virus-induced gene silencing of TaWAK5 in CI12633 plants showed that the silencing of TaWAK5 did not obviously impair wheat resistance to R. cerealis, suggesting that TaWAK5 may be not the major gene in wheat defense response to R. cerealis, or that it is functionally redundant with other genes. This study paves the way for further research into WAK functions in wheat stress physiology.
