Project description:OsNRAMP5 is involved in iron, manganese and cadmium transport. Goal was to determine the effects of knocking down OsNRAMP5 on global rice gene expression.
Project description:OsNRAMP5 is involved in iron, manganese and cadmium transport. Goal was to determine the effects of knocking down OsNRAMP5 on global rice gene expression. Two experiments: Control condition experiment: root or shoot of WT vs. OsNRAMP5 RNAi plants. WT Cd treatment experiment: 4 weeks old WT plants grown under 0 or 10uM Cd for two weeks
Project description:Phosphate starvation/sufficient rice seedling, root or shoot Pi-starvation or Pi-sufficient stresses responsible rice genes, including previously unannotated genes were identified by Illumina mRNA-seq technology. 53 million reads from Pi-starvation or Pi-sufficient root or shoot tissues were uniquely mapped to the rice genome, and these included 40574 RAP3 transcripts in root and 39748 RAP3 transcripts in shoot. We compared our mRNA-seq expression data with that from Rice 44K oligomicroarray, and about 95.5% (root) and 95.4% (shoot) transcripts supported by the array were confirmed expression both by the array and by mRNA-seq, Moreover, 11888 (root) and 11098 (shoot) RAP genes which were not supported by array, were evidenced expression with mRNA-seq. Furthermore, we discovered 8590 (root) and 8193 (shoot) previously unannotated transcripts upon Pi-starvation and/or Pi-sufficient.
Project description:Higher plants have developed sophisticated mechanisms to efficiently acquire and use micronutrients such as copper and iron. In the present work, we studied effects produced by the presence of a wide copper range in growth media and altered copper transport on iron homeostasis in Oryza sativa plants. The global analysis of gene expression in the rice seedlings grown under copper deficiency versus excess in the medium showed an increased expression of the genes involved in iron homeostasis. Different iron-related genes are expressed under either copper deficiency and excess, such as those that encode ferredoxin and transcriptional regulator IRON-RELATED TRANSCRIPTION FACTOR 2 (OsIRO2), respectively. As expected, the expression of OsCOPT1, which encodes a high affinity copper transport protein, was up-regulated under copper deficiency, and the expression of OsIRO2 targets were increased under copper excess. Arabidopsis COPT1 overexpression (C1OE) in rice causes root shortening under copper excess, modifies the expression of the putative Fe-sensing factor HEMERYTHRIN MOTIF-CONTAINING REALLY INTERESTING NEW GENE- AND ZINC-FINGER (OsHRZ1) and enhances the expression of OsIRO2 and its targets, which suggests a role of copper in iron signaling. Our studies conducted under simultaneous copper and iron deficiencies indicate that C1OE plants are more sensitive than the wild-type controls to root growth inhibition. The C1OE rice plants grown on soil contained higher endogenous iron concentration in grains than the wild-type plants (both brown and white grains). The results obtained herein showed the interaction between homeostatic networks of iron and copper, and suggest that strategies to obtain crops with optimized nutrient concentrations in edible parts should take into account this interaction.
Project description:Iron and manganese are part of a small group of transition metals required for photosynthetic electron transport. Here, we present evidence for a functional link between iron and manganese homeostasis. In the unicellular cyanobacterium, Synechocystis sp. PCC 6803 Fe and Mn deprivation resulted in distinct modifications of the function of the photosynthetic apparatus. For example, iron limitation modifies the rate of QA re-oxidation in photosystem II, a complex that contains more Mn than Fe. The intracellular elemental quotas of Fe and Mn are also linked. Fe limitation reduces the intracellular Mn quota. Mn limitation did not exert a reciprocal effect on Fe quotas. Microarray analysis comparing Mn and Fe limitation revealed a stark difference in the extent of the transcriptional response to the two limiting conditions, reflective of the physiological data. The effects of Fe limitation on the transcriptional network are widespread while the effects on Mn limitation are highly specific. Our analysis also revealed an overlap in the transcriptional response of specific Fe and Mn transporters. This overlap provides a framework for explaining Fe limitation induced changes in Mn quotas. Fe transporters can serve as a low affinity Mn transport system. Under iron limitation the specificity of the Fe transport system changes, making it a less efficient Mn transport system. We monitored the gene expression of Synechocystis PCC6083 at standard conditions and after 2 days of iron limitation (0Fe), manganese limitation (0Mn) and combined iron and manganese limitation (0Fe0Mn). Each timepoint and condition was sampled in triplicates. Due to strong deviations in one of the three repeats for the 0Mn and 0Fe0Mn conditions, the corresponding replicates were excluded from further analysis.