Project description:Genetically engineering Nicotiana tabacum 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:Along with lipidomic and metabolomic analyses, we analysed the effect of short-term heat stress on Nicotiana tabacum pollen tubes. Tubes were either grown for 3 hours at room temperature, for 6 hours at room temperature or for 3 hours at room temperature and then 37 °C for another 3 hours.
Project description:We checked the difference of CB-1 and K326 by transcriptomic and metabolomic analysis and found some important genes related to cold stress
Project description:We applied the Illumina HiSeq™ 2000 platform and analyzed differentially expressed genes (DEGs) from untopped and topped plants to study the global changes in gene expression in response to topping. We found that the number of DEGs varied from 7609 to 18,770 based on the reads per kilobase per million mapped reads (RPKM) values. The Gene Ontology (GO) enrichment analysis revealed that the cellular carbohydrate metabolic process and the disaccharide metabolic process, which may contribute to starch accumulation and stress/defense, were overrepresented terms for the DEGs. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that many DEGs were involved in starch and sucrose metabolism, glycolysis/gluconeogenesis, pyruvate metabolism, and plant hormone signal transduction, among other processes. The knowledge gained will improve our understanding of the processes of axillary shoot formation and enlargement at the transcriptional level. This study lays a solid foundation for future studies on molecular mechanisms underlying the growth of axillary shoots.
Project description:The cell death negative regulator, CaRLK1 gene, causes metabolic alterations of pyruvate and alanine via the glyoxylate cycle under hypoxia
Project description:The impact of metabolic engineering on non-target pathways is a poorly explored question that requires deeper mechanistic investigation. Therefore, Nicotiana tabacum was engineered via the chloroplast (C), nuclear (N) or both (CN) genomes to express genes encoding FARNESYL DIPHOSPHATE SYNTHASE (FPS) and SQUALENE SYNTHASE (SQS) to promote squalene biosynthesis. SQS levels were ~4,300-fold higher in C and CN lines than in the N line, but all accumulated ~150-fold more squalene due to substrate or storage limitations. Slower growth and abnormal flowering phenotypes occurred regardless of the compartment or level of transgene expression. Substantial changes in metabolomes of all lines were observed: 65-120 unrelated metabolites changed > 32-fold. Profound effects of transgenesis on non-target gene expression included changes in the expression of 19,076 transcripts by > 2,000-fold in the CN line; 7,784 transcripts by > 1,400-fold in the N line; and 5,224 transcripts by > 2,200-fold in the C line. Cell cycle-associated transcripts were disproportionally repressed in all three lines, as shown by both manual and Gene Ontology analysis, and transporter-related transcripts were induced. Trends observed in transcriptomes were further validated by qRT-PCR. The mechanism underlying these large changes likely involves metabolite-mediated anterograde and/or retrograde signaling.
Project description:The number of known proteins associated with plant lipid droplets (LDs) is small compared to other organelles. Many questions of LD biosynthesis and degradation remain open, also due to lack of candidate LD proteins whose characterization could help to elucidate their function in those processes. We performed a proteomic screen on LDs isolated from Nicotiana tabacum pollen tubes. Proteins that were highly enriched in the LD fraction compared to the total or cytosolic fraction where verified for LD localization via transient expression in tobacco pollen tubes. We also compared the isoforms of typical LD proteins found in the pollen tubes on a qualitative level to the isoforms found in tobacco seeds.
