Project description:To obtain genes expression in different parts of 84k poplar stems, transcriptome sequencing was performed using Illumina Novaseq 6000 second-generation sequencing platform from Shanghai BIOZERON Co. Ltd (www.biozeron.com). Selecte three stem segments of plants REPEAT 1, 2 and 3 with good and similar growth to use: 2nd-3rd internodes (poplar stem top: PST1, PST2, PST3); 9th-10th internodes (poplar stem middle: PSM1, PSM2, PSM3); 14th-15th internodes (poplar stem bottom: PSB1, PSB2, PSB3). [Or the three repeating organisms are also called poplar A, B, C. From top to bottom, the three parts of the stem are also called stem 1, 2, 3.]
Project description:Here we applied a novel approach to isolate nuclei from complex plant tissues (https://doi.org/10.1371/journal.pone.0251149), to dissect the transcriptome profiling of the hybrid poplar (Populus tremula × alba) vegetative shoot apex at single-cell resolution.
Project description:Microarray technology was used to assess transcriptome changes in poplar (Populus alba L.) under a realistic simulation of increased UV-B radiation. Plants were UV-Bbe (UV-B biologically effective radiation) supplemented with a dose of 6 kJ/m2/day for 12 hours per day and allowed to recover during the night. Poplar plants were UV-B treated using a refined controlled environment able to guarantee a realistic simulation of natural conditions, especially for light parameters such as presence of background UV-B radiation for control plants and balanced PAR/UV-A/UV-B ratio. A time course experiment was planned to look both at the rapid and delayed response of poplar to UVB; two time points after 3 h (T3h) and 30 h (6th hour of the third day of treatment, T30h) were considered. 4 independent biological replicates were analysed for each time point. Competitive hybridisations were carried out using the PICME 28K microarray. Keywords: Time course experiment, stress response
Project description:Background Ionic aluminum (mainly Al3+) is rhizotoxic and can be present in acid soils at concentrations high enough to inhibit root growth. Many forest tree species grow naturally in acid soils and often tolerate high concentrations of Al. Previously, we have shown that aspen (Populus tremula) releases citrate and oxalate from roots in response to Al exposure. To obtain further insights into the root responses of aspen to Al, we investigated root gene expression at Al conditions that inhibit root growth. Results Treatment of the aspen roots with 500 µM Al induced a strong inhibition of root growth within 6 h of exposure time. The root growth subsequently recovered, reaching growth rates comparable to that of control plants. Changes in gene expression were determined after 6 h, 2 d, and 10 d of Al exposure. Replicated transcriptome analyses using the Affymetrix poplar genome array revealed a total of 175 significantly up-regulated and 69 down-regulated genes, of which 70% could be annotated based on Arabidopsis genome resources. Between 6 h and 2 d, the number of responsive genes strongly decreased from 202 to 26, and then the number of changes remained low. The responses after 6 h were characterized by genes involved in cell wall modification, ion transport, and oxidative stress. Two genes with prolonged induction were closely related to the Arabidopsis Al tolerance genes ALS3 (for Al sensitive 3) and MATE (for multidrug and toxin efflux protein, mediating citrate efflux). Patterns of expression in different plant organs and in response to Al indicated that the two aspen genes are homologs of the Arabidopsis ALS3 and MATE. Conclusion Exposure of aspen roots to Al results in a rapid inhibition of root growth and a large change in root gene expression. The subsequent root growth recovery and the concomitant reduction in the number of responsive genes presumably reflect the success of the roots in activating Al tolerance mechanisms. The aspen genes ALS3 and MATE may be important components of these mechanisms.