Transcription profiling of Ectocarpus strain Esil32 porophyte and gametophyte stages in normal and mutant strains to analyse expression of two sets of genes previously identified as being putatively sporophyte-specific or gametophyte-specific
ABSTRACT: The aim of this experiment was to analyse the expression of two sets of genes identified as being putatively sporophyte-specific or gametophyte-specific by a suppressive subtraction hybridisation using cDNA from immature sporophytes and immature gametophytes of the Ectocarpus strain Esil32. The expression of these genes was analysed in the sporophyte and gametophyte generations of the life cycle (again using immature algae that had not yet produces zoidangia) and in the sporophyte generation of a mutant strain, immediate upright, that exhibits gametophyte-like characteristics during the sporophyte generation.
Development of the sporophyte and gametophyte generations of the brown alga E. siliculosus involves two different patterns of early development, which begin with either a symmetric or an asymmetric division of the initial cell, respectively. A mutant, immediate upright (imm), was isolated that exhibited several characteristics typical of the gametophyte during the early development of the sporophyte generation. Genetic analyses showed that imm is a recessive, single-locus Mendelian factor and an ...[more]
Project description:The aim of the experiment is to identify Ectocarpus siliculosus (strain Ec32) genes which are up- or down-regulated by auxin. RNAs were extracted from sporophytes treated with auxin NAA 5.10-6M for 30min or 3h, and labelled either with Cy3 or Cy5. Biological triplicates were performed.
Project description:Identification of the régulation pathways implied in adventitious root formation control in Arabidopsis etiolated seedlings. 2 mutants : a null allele and a weak allele of the ARGONAUTE gene. 4 repetitions in 2 pools for each sample.
Project description:Title : Characterization of genes differentially expressed in roots of transgenic arabidopsis lines expressing the p25 protein of beet necrotic yellow vein virus.<br> <br> Biological question : <br> Rhizomania ("crazy root") is a severe disease of sugar beet caused by beet necrotic yellow vein virus (BNYVV), which is transmitted by the soil-inhabiting fungus Polymyxa betae. Symptoms of virus infection are characterized by a constricted tap root and a massive proliferation of fine rootlets that often undergo necrosis. BNYVV RNA-3 encodes a 25 kDa (p25) which is an important determinant of leaf symptom phenotype. It also governs BNYVV invasion of the plant root system and induction of rootlet proliferation in sugar beet.<br> In order to obtain a better understanding of molecular aspects of disease development in roots and to characterize specific host genes involved in response to viral infection, transgenic Arabidopsis overexpressors of p25 viral protein was obtained and better characterized. It was shown that transgenic plants that efficiently expressed p25 protein produced more lateral roots. <br> Comparative analysis (microarray) was performed between wild type Arabidopsis roots and transgenic Arabidopsis roots expressing p25 protein, in order to identify Arabidopsis genes differentially expressed in response to p25 viral protein.<br> <br> Experiment description: <br> Seeds were surface sterilized, chilled at 4C for 4 days, and then germinated and grown on square Petri plates containing sterilized Murashige and Skoog (MS) medium with 1% sucrose. Such stock plates were arranged vertically in plastic racks and placed into growth chamber. After 5 days, plants were transferred carefully onto fresh MS medium big round plates. On each plate, 60 Wild Type (WT) plantlets were transferred on the half right of the plate, and 60 transgenic plantlets (B, E or T lines) were transferred on the half left of the plate. Plates were arranged horizontally and placed into growth chamber. <br> <br>Experiment 1 : 5 plates containing WT0A control plants and B0A transgenic plants. <br> <br>Experiment 2 : 5 plates containing WT1 control plants and B transgenic plants. <br>5 plates containing WT2 control plants and E transgenic plants. <br>5 plates containing WT3 control plants and T transgenic plants. <br> <br>Plants were harvested after 7 days (experiment 1) or 12 days (experiment 2), and WT roots or transgenic roots were pooled and conserved at -80C.
Project description:Inhibition of cellulose synthesis by chemical inhibitors or in a mutant background leads to rapid inhibition of cell elongation. This inhibition appears to be an active process, which involves feedback signalling from the cell wall. We have isolated two loci THE1 and THE2, which are identified by mutations that partially suppress the dark-grown hypocotyl phenotype in a mutant background for cellulose synthase catalytic subunit CESA6_PROCUSTE1. THE1 encodes a receptor kinase and may play a role in this feedback signalling process. To identify genes that are regulated by THE1 and THE2, we compared the transcript profiles of 5 day-old dark-grown seedlings of the1-1_prc1-1 with prc1-1 ; the1-3_prc1-8 with prc1-8 ; prc1-8 or the1-3 with WS and the2-1_prc1-1 with prc1-1.
Project description:The p300 protein is one of more than 15 known mammalian HATs. We have used mice that carry a mutant allele of the p300 gene, which encodes a full-length protein that, however, lacks detectable acetyltransferase (AT)-activity and that acts in a dominant-negative manner. In addition, the allele is conditional, so that it can be expressed in a tissue-specific manner with the help of mice that express Cre-recombinase. Expression of the mutant allele specifically in B-cells, using CD19-cre mice, results in premature death with full penetrance from an autoimmune disease that closely mimics systemic lupus erythematosus (SLE) in its pathological manifestations.
Project description:Cell suspension culture of Arabidopsis thaliana (ecotype Columbia) was treated by 250 mM salicylic acid and by two different concentrations of wortmannin (1 mM and 30 mM) for 4 hours.
Project description:In this experiment, Arabidopsis plants infected by a virus, Tobacco etch virus (TEV), a potyvirus, were compared with healthy plants to identify genes for which the expression is modified by the viral infection. Analysis of both inoculated leaves and upper young leaves were performed 7 days after the inoculation with the virus (or with only buffer for the healthy plants).
Project description:After 5 days of grown in a fresh medium (5% PCV at day0), CdCl2 was added to tested cells (Cad) to a final concentration of 200uM. Nothing was added to control cells (Tem). After 12 and 24 hours of growth +/- cadmium, cells were harvested and frozen in liquid nitrogen.
Project description:Abstract: Testicular cancers in young adult men derive from an inborn precursor lesion, called carcinoma in situ (CIS) of the testis. CIS cells are believed to arise from primordial germ cells or gonocytes that fail to differentiate into the male germ cell lineage, and show a remarkable resemblance to embryonic stem cells (ESC). With this study we aimed at further elucidating the origin of CIS using microarray analysis of genome-wide gene expression. CIS cells only constitute a small fraction of the tissue and therefore, to reduce contaminating RNA from other cell types, we developed a fast (160 sec) staining procedure specific for CIS and fetal germ cells. Highly enriched cell populations were obtained by laser microdissectioning. The expression profiles of CIS cells were compared to microdissected fetal gonocytes, oogonia and cultured ESC with and without genomic amplifications. The cell type most similar to CIS was the gonocytes indicating malignant transformation at this stage. The enriched cell populations allowed us to find unique expression patterns for the developmentally very related cell types. Analyses of the similarities and differences among the cell types may help us understand when and how the malignant transformation to CIS occurs.