Project description:Gluconacetobacter diazotrophicus has been the focus of several studies aiming to understand the mechanisms behind this endophytic diazotrophic bacterium. The present study is the first global analysis of the early transcriptional response of exponentially growing G. diazotrophicus to iron, an essential cofactor for many enzymes involved in various metabolic pathways. RNA-seq, targeted gene mutagenesis and computational motif discovery tools were used to define the G. diazotrophicus Fur regulon. The data analysis showed that genes encoding functions related to iron homeostasis, were significantly upregulated in response to iron limitation. Certain genes involved in the secondary metabolism were overexpressed under iron-limited conditions. In contrast, it was observed that the expression of genes involved in Fe-S cluster biosynthesis, flagellar biosynthesis and type IV secretion systems were downregulated in an iron-depleted culture medium. Our results support a model that control transcription in G. diazotrophicus by Fur function. The G. diazotrophicus Fur protein was able to complement an E. coli fur mutant. These results provide new insights into the effects of iron on the metabolism of G. diazotrophicus, as well as demonstrating the essentiality of this micronutrient for the main characteristic of plant growth promotion by G. diazotrophicus.
2021-01-09 | GSE164445 | GEO
Project description:Transcriptomic analysis of tomato during endophytic bacterial colonisation and humic acid treatment
Project description:Investigation of whole genome gene expression level changes in a Gluconacetobacter xylinus NBRC 3288 delta-fnrG mutant, compared to the wild-type strain.
Project description:The RNA-seq was used to identify differentially regulated miRNAs between a male sterile and wild type tomato during anther development.
Project description:We compared the transcriptomic response of polarized microspore stage tomato anthers to long-term mild heat (LTMH-) stress of wild-type and three lines that display increased pollen thermo-tolerance. Our results indicated distinct differences between the thermo-tolerant lines and wild-type, suggesting a dampened response to LTMH in the tolerant lines than in wild-type.
Project description:Anthocyanins are high value plant antioxidants which are not present in the fruits of cultivated tomato. However, both the dominant gene Anthocyanin fruit (Aft) and the recessive gene atroviolacea (atv), introgressed into domesticated tomato from two different wild Solanum species, stimulate a limited anthocyanin pigmentation. Surprisingly, double mutant Aft/Aft atv/atv tomatoes are characterised by the presence of anthocyanins in the fruit peel, resulting in intensely purple pigmented fruit. We carried out a transcript profiling analysis using GeneChip® Tomato Genome Arrays, in order to identify differentially expressed genes when comparing wild type, Aft/Aft, atv/atv, and Aft/Aft atv/atv fruits. The expression pattern of several genes involved in the anthocyanin pathway was analyzed in detail. Among the fruit peel-associated differentially expressed transcripts, genes involved in phenylpropanoid pathway, cell wall composition, biotic and abiotic stress responses, sugar and hormone metabolism were overrepresented in Aft/Aft atv/atv. Transcriptomic analysis thus revealed that the activation of anthocyanin synthesis in tomato fruit was accompanied by a complex remodulation of gene expression, likely affecting important agronomic and merceological traits. Wild type (Cv. Ailsa Craig, accession number LA2838A), Aft/Aft (accession number LA1996), atv/atv (accession number LA0797) and double mutant (Aft/Aft atv/atv) were grown during the winter season in a controlled heated greenhouse. Fruits were collected at mature green, turning red and red stages of development. The transcriptional profile in Aft/Aft, atv/atv, and Aft/Aft atv/atv fruits when compared to the wild type was analyzed using the GeneChip® Tomato Genome Array.
