Project description:Gene expression profiles before and after spore formation of Lentinula edodes (L54)grown at sawdust. Keywords: time-course SAGE were used to generate tags from RNA of fruit bodies of L. edodes. RNA were extracted from the fruit bodies before and after spore observed. Gene expression profiles of both stages were compared to screen out genes may relate to spore formation.
Project description:The molecular mechanisms regulating the cell fate decision between self-renewal and differentiation/apoptosis in stem and progenitor cells are poorly understood. Here, we report the first comprehensive identification of genes potentially involved in the switch from self-renewal toward differentiation of primary, non-immortalized erythroid avian progenitor cells (T2EC cells). We used the Serial Analysis of Gene Expression (SAGE) technique in order to identify and quantify the genome fraction functionally active in a self-renewing versus a differentiating cell population. We generated two SAGE libraries and sequenced a total of 37,589 tags, thereby obtaining the first transcriptional profile characterization of a chicken cell. Tag identification was performed using a new relational database (Identitag) developed in the laboratory, which allowed a highly satisfactory level of identification. Among 123 differentially expressed genes, 11 were investigated further and for nine of them the differential expression was subsequently confirmed by real-time PCR. The comparison of tag abundance between the two libraries revealed that only a small fraction of transcripts was differentially expressed. The analysis of their functions argue against a prominent role for a master switch in T2EC cells decision-making, but are in favor of a critical role for coordinated small variations in a relatively small number of genes that can lead to essential cellular identity changes. Keywords: other
Project description:Increasing evidence suggests that low-abundant transcripts may play fundamental roles in biological processes. In an attempt to estimate the prevalence of low-abundant transcripts in eukaryotic genomes, we performed a transcriptome analysis in Drosophila using the SAGE technique. We collected 244,313 SAGE tags from transcripts expressed in Drosophila embryonic, larval, pupae, adult, and testicular tissue. From these SAGE tags, we identified 40,823 unique SAGE tags. Our analysis showed that 55% of the 40,823 unique SAGE tags are novel without matches in currently known Drosophila transcripts, and most of the novel SAGE tags have low copy numbers. Further analysis indicated that these novel SAGE tags represent novel low-abundant transcripts expressed from loci outside of currently annotated exons including the intergenic and intronic regions, and antisense of the currently annotated exons in the Drosophila genome. Our study reveals the presence of a significant number of novel low-abundant transcripts in Drosophila, and highlights the need to isolate these novel low-abundant transcripts for further biological studies. Keywords: other
Project description:Undifferentiated human embryonic stem cells grown on mouse embryonic fibroblast feeder layers. HES3 and HES4 are proprietary human ES cell lines of ES Cell International Pte Ltd. Singapore. Keywords: other
Project description:Gene expression profiles at different development stages and different growth medium of Lentinula edodes (L54) are comparied. Keywords: time-course
Project description:We have analyzed the pattern of gene expression in human primary CD34(+) stem/progenitor cells. We identified 42,399 unique serial analysis of gene expression (SAGE) tags among 106,021 SAGE tags collected from 2.5 x 10(6) CD34(+) cells purified from bone marrow. Of these unique SAGE tags, 21,546 matched known expressed sequences, including 3,687 known genes, and 20,854 were novel without a match. The SAGE tags that matched known sequences tended to be at higher levels, whereas the novel SAGE tags tended to be at lower levels. By using the generation of longer sequences from SAGE tags for gene identification (GLGI) method, we identified the correct gene for 385 of 440 high-copy SAGE tags that matched multiple genes and we generated 198 novel 3' expressed sequence tags from 138 high-copy novel SAGE tags. We observed that many different SAGE tags were derived from the same genes, reflecting the high heterogeneity of the 3' untranslated region in the expressed genes. We compared the quantitative relationship for genes known to be important in hematopoiesis. The qualitative identification and quantitative measure for each known gene, expressed sequence tag, and novel SAGE tag provide a base for studying normal gene expression in hematopoietic stem/progenitor cells and for studying abnormal gene expression in hematopoietic diseases. Keywords: other
Project description:SAGE was used to profile gene expression in leukemic myeloid progenitor cells of AML patients with t(8;21), t(15;17), t(9;11) and inv(16). Keywords: SAGE analysis of gene expression in leukemic myeloid progenitor cells isolated from bone marrow Bone marrow cells from 4 patients with de novo t(9;11), 3 with treatment-related t(9;11), and 5 each with inv(16), t(15;17), t(8;21) were used for the study. Each sample contained at least 75% affected cells with no other chromosome abnormalities at cytogenetic level. Mononuclear cells were purified from bone marrow cells for each sample, and CD15+ myeloid progenitor cells were isolated from these mononuclear cells. Poly A+ RNA were isolated from CD15+ myeloid progenitor cells of each sample for SAGE tag collection.
Project description:Sexually dimorphic traits are subject to diversifying selection. Also genes with a male biased gene expression are probably affected by sexual selection and have a high rate of protein evolution. We used SAGE to measure sex biased gene expression in Drosophila pseudoobscura. Consistent with previous results from D. melanogaster, a larger number of genes were male biased (402 genes) than female biased (138 genes). About 34% of the genes changed the sex related expression pattern between D. melanogaster and D. pseudoobscura. Combining gene expression with protein divergence between both species, we observed a striking difference in rate of evolution for genes with a male biased gene expression in one species only. Contrary to expectations, D. pseudoobscura genes in this category showed no accelerated rate of protein evolution, while D. melanogaster genes did. If sexual selection is driving molecular evolution of male biased genes, our data imply a radically different selection regime in D. pseudoobscura. Keywords: SAGE Male and female SAGE libraries of D. pseudoobscura were developed for analyzing the gene expression pattern.
Project description:These libraries represent total RNA from bursal tissue of 20 day old CB-inbred chicks and the ALV induced bursal cell line DT40 Cre1 cells. Keywords = chicken transcriptome SAGE Bursal cell DT40
Project description:These libraries represent Cancer Genome Anatomy Project libraries, which are either produced through CGAP funding, or donated to CGAP. The Cancer Genome Anatomy Project (CGAP: http://cgap.nci.nih.gov) is an interdisciplinary program established and administered by the National Cancer Institute (NCI: http://www.nci.nih.gov) to generate the information and technological tools needed to decipher the molecular anatomy of the cancer cell. This GEO Series was created by the GEO staff as part of a cleanup effort to ensure that all GEO Samples are included within a Series entry.