Project description:Regulation of light absorption under variable light conditions is essential to optimize photosynthetic and acclimatory processes in plants. Light energy absorbed in excess has a damaging effect on chloroplasts and can lead to cell death. Therefore, plants have evolved protective mechanisms against excess excitation energy that include chloroplast accumulation and avoidance responses. One of the proteins involved in facilitating chloroplast movements in Arabidopsis thaliana is the J domain-containing protein required for chloroplast accumulation response 1 (JAC1). The function of JAC1 relates to the chloroplast actin filaments appearance and disappearance. So far, the role of JAC1 was studied mainly in terms of chloroplasts photorelocation. Here, we demonstrate that the function of JAC1 is more complex, since it influences the composition of photosynthetic pigments, the efficiency of photosynthesis, and the CO2 uptake rate. JAC1 has positive effect on water use efficiency (WUE) by reducing stomatal aperture and water vapor conductance. Importantly, we show that the stomatal aperture regulation is genetically coupled with JAC1 activity. In addition, our data demonstrate that JAC1 is involved in the fine-tuning of H2O2 foliar levels, antioxidant enzymes activities and cell death after UV-C photooxidative stress. This work uncovers a novel function for JAC1 in affecting photosynthesis, CO2 uptake, and photooxidative stress responses.
Project description:Genetically engineering Arabidopsis thaliana to express Isoprene Synthase (ISPS) leads to changes in expression of genes assoiated with many growth regulator signaling pathways and signaling networks involved in abiotic and biotic stress responses.
Project description:We performed chloroplast ChIP-seq (cpChIP-seq) to identify the possible DNA-binding sites of mTERF5 in Arabidopsis thaliana. To this end, we generated transgenic Arabidopsis plants expressing mTERF5 carrying an HA tag under the control of the CaMV 35S promoter. Then, We used the polyclonal antibody (abcam, ab9110, lot GR304617-8 ) against HA tag which conjugated to ChIP-Grade protein A/G agarose (Thermo scientific, 26161, lot QJ223903) to perform cpChIP assay. The obtained chromatin immunoprecipitated DNA of chloroplasts were used to build DNA libaries for high-throughput sequencing. Finally, we showed that three potenssial DNA regions across the chloroplast genome compared to the control group were enriched by mTERF5.
Project description:Using whole genome microarray (Affymetrix ATH1) we studied the transcriptional response of Arabidopsis thaliana to glyphosate (Roundup Original) herbicde that inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme and thus disrupts aromaticamino acid biosynthesis. Few genes related to defense and secondary metabolism were altered. Keywords: 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) inhibiting herbicide stress response
Project description:FAR-RED ELONGATED HYPOCOTYL 3 (FHY3) and its homolog FAR-RED IMPAIRED RESPONSE 1 (FAR1) are two transposase-derived transcription factors initially identified as the key components in phytochrome A signaling and recently shown to function in the circadian clock. However, whether FHY3 and FAR1 are involved in other processes of plant development remains largely unknown. Here, we explored chromatin immunoprecipitation-based sequencing (ChIP-seq) analysis to identify 1745 and 1171 FHY3 direct binding target genes in darkness and far-red light conditions, respectively in the Arabidopsis thaliana genome. This analysis revealed that FHY3 preferentially binds to the gene promoters through the previously identified typical FHY3/FAR1 binding motif. Interestingly, FHY3 also binds to two novel motifs in the 178-bp repeats of the Arabidopsis centromere regions in vivo. Comparison between the ChIP-seq and microarray data indicates that FHY3 regulates the expression of 196 and 85 genes in dark and far-red respectively by directly binding to their promoters. FHY3 also co-regulates a number of common target genes with PHYTOCHROME INTERACTING FACTOR 3-LIKE 5 (PIL5) and ELONGATED HYPOCOTYL 5 (HY5). Moreover, our genome-wide identification of FHY3 direct target genes ultimately led to the discovery and validation of a new role of FHY3 in controlling chloroplast development, by directly activating the expression of ACCUMULATION AND REPLICATION OF CHLOROPLASTS5 (ARC5), a key gene regulating chloroplast constriction and division. Taken together, our data suggest that FHY3 is involved in regulating multiple facets of plant development, thus providing new insights into the functions of this type of transposase-derived transcription factors.
Project description:Using whole genome microarray (Affymetrix ATH1) we studied the transcriptional response of Arabidopsis thaliana to triazolopyrimidine (FirstRate) herbicde that inhibits acetolactate synthase (ALS) enzyme and thus disrupts branched chain amino acid biosynthesis. A number of genes related to amino acid, protein metabolism, growth, regulatory networks, respiratory pathways, stress, defense and secondary metabolism were altered. Keywords: Acetolactate synthase (ALS) inhibiting herbicide stress response
Project description:Using whole genome microarray (Affymetrix ATH1) we studied the transcriptional response of Arabidopsis thaliana to imidazolinone (Arsenal) herbicde that inhibits acetolactate synthase (ALS) enzyme and thus disrupts branched chain amino acid biosynthesis. A number of genes related to amino acid, protein metabolism, growth, regulatory networks, respiratory pathways, stress, defense and secondary metabolism were altered. Keywords: Acetolactate synthase (ALS) inhibiting herbicide stress response