Large-scale identification of expressed sequence tags involved in rice and rice blast fungus interaction.
To better understand the molecular basis of the defense response against the rice blast fungus (Magnaporthe grisea), a large-scale expressed sequence tag (EST) sequencing approach was used to identify genes involved in the early infection stages in rice (Oryza sativa). Six cDNA libraries were constructed using infected leaf tissues harvested from 6 conditions: resistant, partially resistant, and susceptible reactions at both 6 and 24 h after inoculation. Two additional libraries were constructed using uninoculated leaves and leaves from the lesion mimic mutant spl11. A total of 68,920 ESTs were generated from 8 libraries. Clustering and assembly analyses resulted in 13,570 unique sequences from 10,934 contigs and 2,636 singletons. Gene function classification showed that 42% of the ESTs were predicted to have putative gene function. Comparison of the pathogen-challenged libraries with the uninoculated control library revealed an increase in the percentage of genes in the functional categories of defense and signal transduction mechanisms and cell cycle control, cell division, and chromosome partitioning. In addition, hierarchical clustering analysis grouped the eight libraries based on their disease reactions. A total of 7,748 new and unique ESTs were identified from our collection compared with the KOME full-length cDNA collection. Interestingly, we found that rice ESTs are more closely related to sorghum (Sorghum bicolor) ESTs than to barley (Hordeum vulgare), wheat (Triticum aestivum), and maize (Zea mays) ESTs. The large cataloged collection of rice ESTs in this study provides a solid foundation for further characterization of the rice defense response and is a useful public genomic resource for rice functional genomics studies.
Jantasuriyarat
Chatchawan
C
Department of Plant Pathology, The Ohio State University, Columbus, Ohio 43210, USA.
Gowda
Malali
M
Haller
Karl
K
Hatfield
Jamie
J
Lu
Guodong
G
Stahlberg
Eric
E
Zhou
Bo
B
Li
Huameng
H
Kim
HyRan
H
Yu
Yeisoo
Y
Dean
Ralph A
RA
Wing
Rod A
RA
Soderlund
Carol
C
Wang
Guo-Liang
GL
D004198:Disease Susceptibility; D020224:Expressed Sequence Tags; D005656:Fungal Proteins / Q000235:genetics; D015723:Gene Library; D017343:Genes, Plant; D007113:Immunity, Innate; D020082:Magnaporthe / Q000235:genetics* / Q000472:pathogenicity; D008969:Molecular Sequence Data; D012275:Oryza / Q000235:genetics* / Q000382:microbiology; D010935:Plant Diseases / Q000235:genetics; D018515:Plant Leaves / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics
D005656:Fungal Proteins; D010940:Plant Proteins