Project description:The plant hormone jasmonic acid (JA) has been known as a signal molecule that is induced by various stresses and mediates plant defense responses. Rice O. sativa inductively produces variety of defensive compounds upon abiotic and biotic stress conditions, such as wounding and insect attack. The bHLH transcription factor RERJ1 has previously been identified as JA-inducible factor whose expression is also rapidly induced by wounding. We identified RERJ1-dependent and wound-inducible genes by comparison with transcriptomes of wound treated wild-type and a Tos17-rerj1 defective mutant rice.
Project description:The plant hormone jasmonic acid (JA) has been known as a signal molecule that is induced by various stresses and mediates plant defense responses. Rice O. sativa inductively produces variety of defensive compounds upon abiotic and biotic stress conditions, such as wounding and insect attack. The bHLH transcription factor RERJ1 has previously been identified as JA-inducible factor whose expression is also rapidly induced by wounding. We identified RERJ1-dependent and wound-inducible genes by comparison with transcriptomes of wound treated wild-type and a Tos17-rerj1 defective mutant rice. Expression profiling between rice leaves of wild-type and tos17-rerj1 mutant treated by wounding for 0, 0.5, 1 and 2 h was compared using two-color method with two biological replicates.
Project description:The plant hormone jasmonic acid (JA) has been known as a signal molecule that is induced by various stresses and mediates plant defense responses. Rice O. sativa inductively produces variety of defensive compounds upon abiotic and biotic stress conditions, such as wounding and insect attack. We identified wound-inducible genes by comparison with transcriptomes between wounded and untreated wild-type rice leaves.
Project description:The plant hormone jasmonic acid (JA) has been known as a signal molecule that is induced by various stresses and mediates plant defense responses. Rice O. sativa inductively produces variety of defensive compounds upon abiotic and biotic stress conditions, such as wounding and insect attack. We identified wound-inducible genes by comparison with transcriptomes between wounded and untreated wild-type rice leaves. Expression profiling in wild-type rice leaves treated by wounding for 0.5, 1, 2 and 4 h was compared with that in untreated control using two-color method with two biological replicates.
Project description:Flowering time is an important factor determining yield and seed quality in maize. A change in flowering time is a strategy used to survive abiotic stresses. Among abiotic stresses, drought can increase anthesis-silking intervals (ASI), resulting in negative effects on maize yield. We have analyzed the correlation between flowering time and drought stress using RNA-seq and bioinformatics tools. Our results identified a total of 619 genes and 126 transcripts whose expression was altered by drought stress in the maize B73 leaves under short-day condition. Among drought responsive genes, we also identified 20 genes involved in flowering times. Gene Ontology (GO) enrichment analysis was used to predict the functions of the drought-responsive genes and transcripts. GO categories related to flowering time included reproduction, flower development, pollen-pistil interaction, and post-embryonic development. Transcript levels of several genes that have previously been shown to affect flowering time, such as PRR37, transcription factor HY5, and CONSTANS, were significantly altered by drought conditions. Furthermore, we also identified several drought-responsive transcripts containing C2H2 zinc finger, CCCH, and NAC domains, which are frequently involved in transcriptional regulation and may thus have potential to alter gene expression programs to change maize flowering time. Overall, our results provide a genome-wide analysis of differentially expressed genes (DEGs), novel transcripts, and isoform variants expressed during the reproductive stage of maize plants subjected to drought stress and short-day condition. Further characterization of the drought-responsive transcripts identified in this study has the potential to advance our understanding of the mechanisms that regulate flowering time under drought stress.
Project description:A submergence tolerant indica rice cultivar FR13A, was also reported to withstand salt stress and proven in our experiments. The mechanism of tolerance is yet to be studied by forward genetics approach. However, it is known that salt stress tolerance is governed by several QTLs and not by a single gene. To understand the mechanism of such a complex mechanism of salt tolerance we selected, two indica rice genotypes namely, I) FR13A, a tolerant indica variety and ii) IR24, a susceptible genotype for this study. We used the 22K rice Oligoarray from Agilent technologies to study the transcript profile in the leaves of the two contrasting rice genotypes under constitutive and salt stress conditions at seedling stage. Keywords: Mechanism of salt tolerance
Project description:During evolution, plants evolved various reactions to wounding. Fast wound sealing and subsequent healing represent a selective advantage of particular importance for plants growing in arid habitats. An effective self-sealing function by internal deformation has been found in the succulent leaves of Delosperma cooperi. After a transversal incision, the entire leaf bends until the wound is closed. Our results indicate that the underlying sealing principle is a combination of hydraulic shrinking and swelling as the main driving forces and growth-induced mechanical pre-stresses in the tissues. Hydraulic effects were measured in terms of the relative bending angle over 55 minutes under various humidity conditions. The higher the relative air humidity, the lower the bending angle. Negative bending angles were found when a droplet of liquid water was applied to the wound. The statistical analysis revealed highly significant differences of the single main effects such as "humidity conditions in the wound region" and "time after wounding" and their interaction effect. The centripetal arrangement of five tissue layers with various thicknesses and significantly different mechanical properties might play an additional role with regard to mechanically driven effects. Injury disturbs the mechanical equilibrium, with pre-stresses leading to internal deformation until a new equilibrium is reached. In the context of self-sealing by internal deformation, the highly flexible wide-band tracheids, which form a net of vascular bundles, are regarded as paedomorphic tracheids, which are specialised to prevent cell collapse under drought stress and allow for building growth-induced mechanical pre-stresses.