Project description:Global gene expression was compared between Arabidopsis lines with altered expression of ANAC102 (over-expressed and knocked-out) and wild-type. ANAC102 is a putative NAC domain transcription factor. Gene expression was compared between an ANAC102 over-expressing line and parental ecotype C24 under ambient atmosphere to determine which genes ANAC102 is capable of regulating. Gene expression was also compared between three week old plants of an ANAC102 knock-out line and parental ecotype Col-0 under 0.1% Oxygen and ambient atmosphere conditions to determine which genes may require ANAC102 for appropriate expression under these conditions. Gene expression was also compared between imbibed seeds of an ANAC102 knock-out line and parental ecotype Col-0 following a 0.1% Oxygen treatment. Keywords: Genetic modification
Project description:HRE1 and HRE2 are two ERF transcription factors induced by low oxygen. In this work we analyzed the effect of ectopic expression of HRE1 and HRE2 on the arabidopsis transcriptome in aerobic and hypoxic (1% O2) conditions. While HRE1 has a moderate effect on the expression of anaerobic genes under hypoxia, HRE2 does not affect them either under aerobic or hypoxic conditions.
Project description:Adult human dermal fibroblasts reside in vivo under low oxygen tension. Thus, low oxygen culture conditions represent a physiological state for adult human dermal fibroblasts. We have also previously shown that low oxygen and addition of basic fibroblast growth factor (FGF2) lead to prolonged life-span of adult human dermal fibroblasts. Therefore, we set to determine effects of low oxygen and FGF2 on the gene expression signature of adult human dermal fibroblasts. This global analysis will allow identification of genes affected and pathways regulated by low oxygen and FGF2.
Project description:Investigation of mRNA expression level changes in S. pombeOfd2 (SPAP8A3.02c) deletion strain compared to wild-type strain at both normal oxygen (normoxia) and low oxygen (hypoxia) growth conditions. Four samples in total consisting of two S. pombeyeast strains, wild type (WT) and a gene deleted strain for Ofd2 (SPAP8A3.02c), analysed for gene expression under two growth conditions, normal oxygen (normoxia) and low oxygen (hypoxia). Five micrograms of total RNA from two independent experiments were pooled and mRNA levels were quantified by Roche NimbleGen using the S. pombe 72K array service
Project description:Expression profiling of A. thaliana, A. stelleri, R. islandica, and T. salsuginea under the low-oxygen treatment(0.1% O2/99.9% N2, various time points at 0, 1, 3, 8, 24, 72h) Comparative analysis of transcriptional responses to low-oxygen stress with Arabidopsis and its related species to gain comprehensive insights into low-oxygen responses of the species.
Project description:Senescent is an irreversible form of cell cycle arrest initiated by damaged cell constituents and subsequent pro-oncogenic signaling. Replicative senescence in vitro can be considered a model for human aging. When fibroblasts are cultured under atmospheric oxygen conditions of 20%, typical of normal tissue culture procedure, fibroblasts generally reach their replicative capacity at 50-60 population doublings (PDs). When fibroblasts are cultured under normal physiological oxygen conditions of 3%, PDs increase about 30% relative to atmospheric levels. Hence while oxygen is a requirement for normal aerobic respiration, it can contribute to the total amount of oxidative stress to which cells are exposed to, leading to a long-term adverse effect in vitro. Inasmuch, cultures maintained under hyperoxic and hypoxic conditions provide a convenient model system for assessing the relationship between oxygen/oxidative stress and senescence. We used microarrays to profile the changes in global gene expression during aging and senescence of Imr90 cells under growth oxygen conditions of 3% and 20%.
Project description:Senescent is an irreversible form of cell cycle arrest initiated by damaged cell constituents and subsequent pro-oncogenic signaling. Replicative senescence in vitro can be considered a model for human aging. When fibroblasts are cultured under atmospheric oxygen conditions of 20%, typical of normal tissue culture procedure, fibroblasts generally reach their replicative capacity at 50-60 population doublings (PDs). When fibroblasts are cultured under normal physiological oxygen conditions of 3%, PDs increase about 30% relative to atmospheric levels. Hence while oxygen is a requirement for normal aerobic respiration, it can contribute to the total amount of oxidative stress to which cells are exposed to, leading to a long-term adverse effect in vitro. Inasmuch, cultures maintained under hyperoxic and hypoxic conditions provide a convenient model system for assessing the relationship between oxygen/oxidative stress and senescence. We used microarrays to profile the changes in global gene expression during aging and senescence of Imr90 cells under growth oxygen conditions of 3% and 20%. Imr90 cells at various population doubling timepoints (young, old, and senescent) grown separately under 3 and 20% oxygen growth conditions were selected for RNA extraction and hybridization on Affymetrix microarrays. Timepoints from cells grown under 3% and 20% oxygen conditions were age matched via population doublings to ensure accurate cross sample comparison.
Project description:Low R:FR signaling through phytochromes induces shade avoidance responses, including petiole elongation. Salicylic acid-mediated defense against pathogens is inhibited under these conditions. Using microarrays we studied the crosstalk between low R:FR and SA at the global gene expression level in Arabidopsis thaliana.