Project description:Lesion mimic mutants in rice are widely known as spotted leaf (spl) mutants, of which several genotypes exhibit enhanced resistance to different races of Magnaporthe grisea. Besides naturally occurring spotted leaf mutants, tissue culture-induced reverse genetic repositories also act as sources of lesion mimic mutants in rice. We systematically evaluated a large collection of Tos17 mutant panel lines, developed and maintained at the National Institute of Agrobiological Sciences, Tsukuba, Japan, for their reaction to three different races of M. grisea and identified a lesion mimic mutant, NF4050-8, that showed lesions similar to naturally occurring spl5 mutant and enhanced resistance to all three blast races tested. Microarray analysis of ~44,000 rice genes in NF4050-8 with Nipponbare as control during the progressive lesion appearance stage revealed significant up-regulation of numerous defense/pathogenesis-related genes as well as several WRKY domain-containing genes and down-regulation of haem peroxidase gene. Subsequent real-time PCR analysis of WRKY45 and PR1b genes in NF4050-8 and spl5 suggested possible constitutive activation of a defense signaling pathway downstream of Salicylic Acid (SA) but independent of NH1 in these mutant lines of rice.
Project description:Lesion mimic mutants in rice are widely known as spotted leaf (spl) mutants, of which several genotypes exhibit enhanced resistance to different races of Magnaporthe grisea. Besides naturally occurring spotted leaf mutants, tissue culture-induced reverse genetic repositories also act as sources of lesion mimic mutants in rice. We systematically evaluated a large collection of Tos17 mutant panel lines, developed and maintained at the National Institute of Agrobiological Sciences, Tsukuba, Japan, for their reaction to three different races of M. grisea and identified a lesion mimic mutant, NF4050-8, that showed lesions similar to naturally occurring spl5 mutant and enhanced resistance to all three blast races tested. Microarray analysis of ~44,000 rice genes in NF4050-8 with Nipponbare as control during the progressive lesion appearance stage revealed significant up-regulation of numerous defense/pathogenesis-related genes as well as several WRKY domain-containing genes and down-regulation of haem peroxidase gene. Subsequent real-time PCR analysis of WRKY45 and PR1b genes in NF4050-8 and spl5 suggested possible constitutive activation of a defense signaling pathway downstream of Salicylic Acid (SA) but independent of NH1 in these mutant lines of rice. We used Agilent rice oligo microarrays to identify putative defense/pathogenesis-related genes. Leaf tissues of the rice genotypes Nipponbare and NF4050-8 were used in the study. Two replications of microarray experiments were carried out by hybridizing the cRNA from control and progressive lesion appearance stage on 4 x 44k microarray.
Project description:The rice lesion mimic, spotted leaf 5 (spl5), created by γ-ray radiation, has spontaneous HR-like lesions on its leaves and shows enhanced resistance to rice blast and bacterial blight pathogens. Some genes were differentially expressed in this mutant compared with its WT control ZF802, and these genes were also associated with some important signaling pathways, such as defense response, oxidation-reduction process and stress response. We analyzed the transcriptional profiling of spl5 mutant and WT using the microarray, in order to reveal the signal pathway of SPL5 gene in regulation of disease resistance.
Project description:The rice lesion mimic, spotted leaf 5 (spl5), created by M-NM-3-ray radiation, has spontaneous HR-like lesions on its leaves and shows enhanced resistance to rice blast and bacterial blight pathogens. Some genes were differentially expressed in this mutant compared with its WT control ZF802, and these genes were also associated with some important signaling pathways, such as defense response, oxidation-reduction process and stress response. We analyzed the transcriptional profiling of spl5 mutant and WT using the microarray, in order to reveal the signal pathway of SPL5 gene in regulation of disease resistance. Rice leaves were selected at lesion stages of spl5 mutant for RNA extraction and hybridization on Affymetrix microarrays. The lesions in rice leaves were belong to HR phenotype, which was one of the important reasons for rice disease resistance. In order to realize which genes were associated with the degree of lesions and mediated the disease resistance, we put the leaves of spl5 mutant into two categories, based on the degree of lesion formation: few lesions (FL), leaf area with 10-20% lesions and many lesions (ML), leaf area with 70-80% lesions.
Project description:To understand the dynamics and global gene reprogramming in the early response to mechanical wounding in rice, the transcriptional response to mechanical injury was analyzed. A time-course experiment revealed the highly dynamic nature of the wound response in rice. Mechanical wounding triggered extensive gene expression reprogramming in the locally wounded leaf, affecting various physiological processes, including defense mechanisms and potentially tissue repair and regeneration. The rice response to mechanical wounding displayed both differences and similarities compared to the response to jasmonate treatment. These results highlight the importance of early JA signaling in response to mechanical stress in rice. This analysis provides an overview of the global transcriptional response to mechanical stress in rice, offering valuable insights for future studies on rice's response to injury, insect attack, and abiotic stresses.
Project description:In this study, we examined the transcriptome dynamics within the matured fully expanded rice leaf and used strand-specific RNA sequencing to generate a comprehensive transcriptome dataset for the mature rice leaf. The rice Nipponbare (Oryza sativa l. japonica) seedlings were grown in the greenhouse. About 20 days after planting, the fully opened 4th leaves was cut it into seven 3-cm segments, from bottom to tip and labeled as sections 1 to 7, respectively. The tissues were immediately frozen in liquid nitrogen for total RNA extraction. Two biological replicates were collected for each section. Note: All samples in SRA were assigned the same sample accession (SRS685294). This is incorrect as there are different samples, hence âSource Nameâ was replaced with new values. Comment[ENA_SAMPLE] contains the original SRA sample accessions.