To mimic natural flooding conditions, we have adopted an open system treatment, in which only roots are subjected to hypoxia treatment. Using microarray analysis, we identified a number of AP2/ERF genes in Arabidopsis that are induced at different stages of hypoxia treatment.
No associated publication
Specimen part, Treatment
View SamplesDue to limited bio-availability of Fe, plants evolved adaptive alterations in development regulated at the transcriptional level. We investigated the early transcriptional response to Fe deficiency.
Early iron-deficiency-induced transcriptional changes in Arabidopsis roots as revealed by microarray analyses.
Specimen part
View SamplesThe environmental light plays a vital role in regulating the plant growth and development. Transcriptomic profilings were widely used to examine how light regulates the changes of mRNA populations at a genome-wide scale. However, it remains unclear if translational regulation represents a new dimension of gene expression regulation in response to the light signal. Through a transcriptomic comparison of steady-state and polysome-bound mRNAs, we revealed an increased translational efficiency in de-etiolating Arabidopsis seedlings. Over 3,500 genes are subjected to translational regulation whereas only about 770 genes have increased mRNA abundances in response to the light signal. This result suggests a stronger impact of translational control over transcriptomic changes during photomorphogenesis. Genes encoding ribosomal protein are preferentially regulated at the translational level, possibly contributing to the enhancement of translation efficiency as observed. We also uncovered mRNAs regulated at the translational level share characteristics of longer half-lives and shorter cDNA length. The presence of a cis-element, TAGGGTTT, in the 5untranslated region of a transcript renders its translational regulation by light signals. Taken together, our study revealed a previously neglected aspect of gene expression regulation during Arabidopsis photomorphogenesis. The identities and molecular signatures associated with mRNAs regulated at the translational level also offer new directions to perform mechanistic studies of light-trigged translational enhancement in Arabidopsis.
Widespread translational control contributes to the regulation of Arabidopsis photomorphogenesis.
Specimen part, Treatment, Time
View SamplesCsUBC13 was identified via proteomics from iron starvation treated Cucumber root. ubc13A is an ABRC seed stock (CS51269). CS851269 was purchased from ABRC and confirmed as homozygous Atubc13A knock-out T-DNA mutant. We generated transgenic arabidopsis with ectopic expression of CsUBC13 gene under control of the cauliflower 35S promotor. Both genotypes and Col-0 were used to investigate the transcriptional response to Iron (Fe) deficiency.
A lysine-63-linked ubiquitin chain-forming conjugase, UBC13, promotes the developmental responses to iron deficiency in Arabidopsis roots.
Specimen part
View SamplesWe have reported that JMJ17 act as a repressor to a set of genes involved in photosynthesis, tetrapyrrole biosynthesis and light response related development in the dark, while during dark to light irradiation it acts as an activator of same set of genes.
No associated publication
Specimen part, Treatment
View SamplesPlants can be primed by a stress cue to mount a faster and stronger activation of defense mechanisms upon a subsequent stress. A crucial component of such stress priming is the modified reactivation of genes upon recurring stress, a phenomenon known as transcriptional memory. The transcriptional memory in response to heat stress is not clear at the genome scale.
Distinct heat shock factors and chromatin modifications mediate the organ-autonomous transcriptional memory of heat stress.
Age, Specimen part
View SamplesPluripotent stem cells, including human embryonic stem (hES) and induced pluripotent stem (hiPS) cells, have been regarded as useful sources for cell?based transplantation therapy. However immunogenicity of the cells remains the major determinant for successful clinical application. We report the examination of several hES cell lines (NTU1 and H9), hiPS cell lines, and their derivatives (including stem cell?derived hepatocytes) for the expression of major histocompatibility complex (MHC), natural killer (NK) cell receptor (NKp30, NKp44, NKp46) ligand, immune?related genes, human leukocyte antigen (HLA) haplotyping, and the effects in functional mixed lymphocyte reaction (MLR). Flow cytometry showed lower levels (percentages and fluorescence intensities) of MHC class I (MHC?I) molecules, 2?microglobulin and HLA?E in undifferentiated stem cells, but the levels were increased after co?treatment with interferon gamma and/or in vitro differentiation. Antigen presenting cell markers (CD11c, CD80 and CD86) and MHC?II (HLA?DP, DQ and DR) remained low throughout the treatments. Recognitions of stem cells/derivatives by NK lysis receptors were lower or absent. Activation of responder lymphocytes was significantly lower by undifferentiated stem cells than by allogeneic lymphocytes in MLR, but differentiated NTU1 hES cells induced a cell number?dependent lymphocyte proliferation comparable with that by allogeneic lymphocytes. Interestingly activation of lymphocytes by differentiated hiPS cells or H9 cells became blunted at higher cell numbers. Real?time RT?PCR showed significant differential expression of immune privilege genes (TGF?2, Arginase 2, Indole 1, GATA3, POMC, VIP, CALCA, CALCB, IL?1RN, CD95L, CR1L, Serpine 1, HMOX1, IL6, LGALS3, HEBP1, THBS1, CD59 and LGALS1) in pluripotent stem cells/derivatives when compared to somatic cells. It is concluded that pluripotent stem cells/derivatives are predicted to be immunogenic, though evidences suggest some levels of potential immune privilege. In addition, differential immunogenicity may exist between different pluripotent stem cell lines and their derivatives
Characteristic expression of major histocompatibility complex and immune privilege genes in human pluripotent stem cells and their derivatives.
Sex, Specimen part
View SamplesHSFA1s are a gene family of HSFA1 with four members, HSFA1a, HSFA1b, HSFA1d, and HSFA1e. HSFA1s are the master regulators of heat shock response. As a part of the heat shock response, HSFA2 can prolong the heat shock response and amplify the heat shock response in response to repeat heat shock. To identify the heat-shock-responsive genes differentially regulated by HSFA1s and HSFA2, we compared the transcriptomic differences of plants containing only constitutively expressed HSFA1s or HSFA2 after heat stress.
Common and distinct functions of Arabidopsis class A1 and A2 heat shock factors in diverse abiotic stress responses and development.
Age, Specimen part
View Samplesa novel orphan peptide, IRON-REGULATED PROTEIN1 (IRP1) that is rapidly induced by Fe deficiency and improves growth on Fe-deplete media.
No associated publication
Specimen part
View SamplesWe isolated the glucose-inhibited root elongation1 (gir1) mutant from a genetic screen of activation T-DNA tagged seeds grown on 6% glucose agar plates. The gir1 mutant showed short swollen root phenotype at the presence of glucose and had a sever sterility when grown in soil. To better understand the molecular basis of GIR1-mediated gene expression, the Affymetrix ATH1 GeneChip was used to analyze the gene expression profiling in the gir1 mutant. The results showed that cell wall, carbohydrate, and lipid metabolic or transporter-related genes were altered expression pattern. These data suggest that GIR1 regulates root and flower growth and development through cell wall modification and, perhaps, membrane trafficking.
No associated publication
Specimen part
View Samples