Transcription profiling of fusiform cambial and ray cambial cells from poplar trees
ABSTRACT: (paper abstract) Wood is a renewable resource that serves as a sustainable raw material for energy, fuels and materials. A basic understanding of the cambial meristem and the origin of wood cells is critical for forest tree molecular breeding to increase the availability of woody raw materials. Gene expression per cell type in the cambium of poplar (Populus trichocarpa x P. deltoïdes cultivar Boelare) was investigated using poplar microarray. Cells were hand microdissected from lyophilized sections of vascular cambial zone sampled in growing poplar. Two cell types were isolated, fusiform cambial cells (FCCs) and ray cambial cells (RCCs). Results showed about one thousand genes differentially expressed per cell type. Microarray expression results were validated by a second cell sampling used for reverse northern dot blot and RT-PCR analysis. RCCs revealed specific photosynthetic competences involving at least 35 genes of the photosystems. RCCs revealed also a marked difference for intercellular transport involving notably aquaporin genes. Distinct classes of cell-wall related genes were detected in RCCs and FCCs. A candidate xyloglucan endotransglycosylase showed to be upregulated and highly expressed in FCCs and an extensin family gene was also very highly expressed in these cells. A candidate polygalacturonase was strikingly expressed specifically in RCCs. A marked expression of cytoskeleton genes was also reported for FCCs where profilin family genes were very highly expressed. Related to cell signaling and regulation, one of the most intriguing result was the observation of LAX1 gene specificity in FCCs whereas PIN genes were expressed in both cell types.
INSTRUMENT(S): G2565AA DNA microarray scanner [Agilent]
Project description:The current project is within the range of molecular immunogenetic auto immune diseases and refers to the comparative study of promiscuous gene expression of tissue-specific antigens (TSAs) in the thymus of NOD mice line (non obese diabetic) who plays the auto-immune diabetes mellitus type 1, during the transition from state pre-diabetics to diabetics. Use the technology of oligo arrays to investigate the expression of miRNAs and cDNA microarrays to investigate the expression of genes encoding the messenger RNAs including TSAs (tissue specific antigens).
Project description:Baseline gene expression in circulating peripheral blood mononuclear cells isolated from 18 apparently healthy volunteers (10 females and 8 males). The volunteers fasted overnight for 10 hours prior to collection of blood samples (but they were allowed water). 5 blood samples were collected from each volunteer at consecutive 8-day intervals. Volunteers were included in this study provided they met the following selection criteria, that they should be <br>Aged between 20 and 45 years of age; <br>A non-smoker (or an ex-smoker);<br>Not pregnant or been pregnant in the last 12 months <br>Not diagnosed with any long-term medical condition; <br>Or have not (in the previous 4 months) donated blood, received any inoculations and are not taking regular prescribed medicine (including HRT and oral contraception) <br>Prior to inclusion in this study volunteers were screened for general health and had a blood sample taken for routine screening of Hb content etc. Only those volunteers who were in good general health were allowed to participate in the study. <br>The age of all volunteers has been reported here as being 20-45 years in order to preserve the anonymity of the data, and so that the individuals involved may not be able to track down their own specific data. Please contact us if the details of volunteers' ages are required.
Project description:Umbilical cord mesenchymal stem cells were stimulated to osteogenesis by 24h, 48h and 7 days. Undifferentiated and treated cells have their total RNA extracted and 25 ug were used to extract micro RNAs by Flash PAGE Fractionator (Ambion). These miRNA were labeled and used to hybridize to 662 oligo arrays corresponding to miRNA sequences from human, rat and mouse. The hybridized slides were scanned in the Amersham Automatic Slide Processor, quantified by TIGR Spotfinder software and submitted to stathiscal treatment in TIGR MEV software.
Project description:The time course experiment was designed as follow: (1) Mesenchymal stem cell (indifferentiated cells)/ time 0h; (2) After 24 h of osteogenic induction; (3) After 48 h of osteogenic induction (4) After 7 days of osteogenic induction.
Project description:C3H/HeH females were mated with 101/H males<br><br>Mating was assessed by the presence of vaginal plugs the next morning. Identification of plug was designated day 0.5.<br><br> <br><br>At 8.5 days of development the dam was culled by cervical dislocation, the uterine horns disscted and placed into PBS. The uterus was dissected to release decuduae and these opened according to standard protocols. Morphologically normal looking embryos of between 4 and 6 somites were collected. The left and right lateral plates were dissected away with watchmakers forceps and pools of 4 left and 4 right lateral plates were snap frozen in LN2.
Project description:Phenotypic plasticity, the ability of one genotype to express different phenotypes in response to changing environmental conditions, is one of the most common phenomena characterising the living world and is not only relevant for the ecology but also for the evolution of species. Daphnia, the waterflea, is a textbook example for predator induced phenotypic plastic defences including changes in life-history, behaviour and morphology. However, the analysis of molecular mechanisms underlying these inducible defences is still in its early stages.<br><br>We exposed Daphnia magna to chemical cues of the predator Triops cancriformis to identify key processes underlying plastic defensive trait formation. D. magna is known to develop an array of morphological changes in the presence of T. cancriformis including changes of carapace morphology and cuticle hardening. To get a more comprehensive idea of this phenomenon, we studied four different genotypes originating from habitats with different predation history, reaching from predator-free to temporary habitats containing T. cancriformis.<br><br>We analysed the morphologies as well as proteomes of predator-exposed and control animals. Three genotypes showed morphological changes when the predator was present. Using a high-throughput proteomics approach, we found 294 proteins which were significantly altered in their abundance after predator exposure in a general or genotype dependant manner. Proteins connected to genotype dependant responses were related to the cuticle, protein synthesis and calcium binding whereas the yolk protein vitellogenin increased in abundance in all genotypes, indicating their involvement in a more general response. Furthermore, genotype dependant responses at the proteome level correlated well with local adaptation to Triops predation.<br><br>Altogether, our study provides new insights concerning genotype dependant and general molecular processes involved in predator-induced phenotypic plasticity in D. magna.
Project description:Dosage compensation ensures that males and females, despite unequal number of X chromosomes, equalize for X linked gene expression. In Drosophila, it is achieved by a two-fold up-regulation of most of the genes present on the male X chromosome, and requires the association of the Dosage Compensation Complex (DCC) on the X chromosome. One of the main intriguing aspects of dosage compensation is how this complex is able to target specifically hundreds of sites only on the X chromosome in order to ensure dosage compensation. In order to better understand the targeting of the DCC and the dosage compensation mechanism, we have then decided to analyze the distribution of the DCC as well as the expression levels in male and female in a more complete and precise manner, using microarrays. In this experiment, we present the data used to analyse the distribution of the MSL-1 and MSL-3 protein (part of the DCC complex) on the X chromosome in WT embryos aged from 0H-14H, as well as the distribution of MSL-1 in embryos aged from 4-6H and in male III instar salivary glands. The DNA amplified from the specific immunoprecipitation (MSL-1 or MSL-3 IP) were labelled using Cy5-dCTP and hybridized against DNA amplified from a non specific immunoprecipitation (mock IP), labeled with Cy3 dye. In parralel we present the data used to analyse the expression profile of X-linked genes in WT male or female III instar larvae salivary glands. The cDNA amplified from the RNA extracted from the male or female salivary glands were labelled using Cy5-dUTP and hybridized against the reference sample, labelled with Cy3-dUTP (pool RNA from ON embryos, adultes, and salivary glands mixed at a ratio 1:1:1.and amplified as the RNA from salivary glands). We used for this study a cDNA array developed by the Genecore facility in EMBL, covering the DGC1 and DGC2 cDNA libraries from the Berkeley Drosophila Genome Project, which represents more than 70% of the coding Drosophila genome.