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cDNA Microarray Technology (cdna + microarray_technology)
Selected AbstractsEVOLUTION OF INSECT METAMORPHOSIS: A MICROARRAY-BASED STUDY OF LARVAL AND ADULT GENE EXPRESSION IN THE ANT CAMPONOTUS FESTINATUSEVOLUTION, Issue 4 2005Michael A. D. Goodisman Abstract Holometabolous insects inhabit almost every terrestrial ecosystem. The evolutionary success of holometabolous insects stems partly from their developmental program, which includes discrete larval and adult stages. To gain an understanding of how development differs among holometabolous insect taxa, we used cDNA microarray technology to examine differences in gene expression between larval and adult Camponotus festinatus ants. We then compared expression patterns obtained from our study to those observed in the fruitfly Drosophila melanogaster. We found that many genes showed distinct patterns of expression between the larval and adult ant life stages, a result that was confirmed through quantitative reverse-transcriptase polymerase chain reaction. Genes involved in protein metabolism and possessing structural activity tended to be more highly expressed in larval than adult ants. In contrast, genes relatively upregulated in adults possessed a greater diversity of functions and activities. We also discovered that patterns of expression observed for homologous genes in D. melanogaster differed substantially from those observed in C. festinatus. Our results suggest that the specific molecular mechanisms involved in metamorphosis will differ substantially between insect taxa. Systematic investigation of gene expression during development of other taxa will provide additional information on how developmental pathways evolve. [source] Identification of genes involved in radiation-induced G1 arrest,JOURNAL OF CHEMOMETRICS, Issue 10-11 2007Giuseppe Musumarra Abstract The advent of microarray gene expression technology permits the simultaneous analysis of the levels of expression of thousands of genes and provides large dataset requiring multivariate analysis tools. Multiple genetic factors may modulate the occurrence and magnitude of the arrest in the G1 phase of the cell cycle following exposure to ionizing radiation in human tumour cell lines. The ability to G1 arrest after exposure to gamma rays and the global gene expression profile, evaluated by cDNA microarray technology, have been reported for the National Cancer Institute (NCI) 60 tumour cell lines panel. The sensitivity of the tumour cell lines to radiations represents an activity fingerprinting that can be correlated by partial least squares (PLS) to the transcriptional profiles of the same cell lines. VIP values obtained by the PLS method are able to detect transcripts relevant to the radiation-induced G1 arrest. High VIP values were obtained for the basal levels of transcripts such as p21/Waf1/Cip1 and MDM2, that are well known for their roles in G1 arrest after irradiation. Novel functional relationships suggested by high VIP values can be investigated experimentally. As an example, in the present study, we report that the transcript for the FLJ11046 protein is induced dose-dependently by gamma-irradiation in a cell line with mutated p53, but not in cell lines with wild-type p53. Moreover specific silencing of FLJ11046 transcript by RNA interference technology results in a block of cell growth. Copyright © 2007 John Wiley & Sons, Ltd. [source] Molecular fingerprinting of TGFß-treated embryonic maxillary mesenchymal cellsORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 4 2003M.M. Pisano Abstract The transforming growth factor-ß (TGFß) family represents a class of signaling molecules that plays a central role in normal embryonic development, specifically in development of the craniofacial region. Members of this family are vital to development of the secondary palate where they regulate maxillary and palate mesenchymal cell proliferation and extracellular matrix synthesis. The function of this growth factor family is particularly critical in that perturbation of either process results in a cleft of the palate. While the cellular and phenotypic effects of TGFß on embryonic craniofacial tissue have been extensively cataloged, the specific genes that function as downstream mediators of TGFß in maxillary/palatal development are poorly defined. Gene expression arrays offer the ability to conduct a rapid, simultaneous assessment of hundreds to thousands of differentially expressed genes in a single study. Inasmuch as the downstream sequelae of TGFß action are only partially defined, a complementary DNA (cDNA) expression array technology (Clontech's AtlasTM Mouse cDNA Expression Arrays), was utilized to delineate a profile of differentially expressed genes from TGFß-treated primary cultures of murine embryonic maxillary mesenchymal cells. Hybridization of a membrane-based cDNA array (1178 genes) was performed with 32P-labeled cDNA probes synthesized from RNA isolated from either TGFß-treated or vehicle-treated embryonic maxillary mesenchymal cells. Resultant phosphorimages were subject to AtlasImageTM analysis in order to determine differences in gene expression between control and TGFß-treated maxillary mesenchymal cells. Of the 1178 arrayed genes, 552 (47%) demonstrated detectable levels of expression. Steady state levels of 22 genes were up-regulated, while those of 8 other genes were down-regulated, by a factor of twofold or greater in response to TGFß. Affected genes could be grouped into three general functional categories: transcription factors and general DNA-binding proteins; growth factors/signaling molecules; and extracellular matrix and related proteins. The extent of hybridization of each gene was evaluated by comparison with the abundant, constitutively expressed mRNAs: ubiquitin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ornithine decarboxylase (ODC), cytoplasmic beta-actin and 40S ribosomal protein. No detectable changes were observed in the expression levels of these genes in response to TGFß treatment. Gene expression profiling results were verified by Real-Time quantitative polymerase chain reaction. Utilization of cDNA microarray technology has enabled us to delineate a preliminary transcriptional map of TGFß responsiveness in embryonic maxillary mesenchymal cells. The profile of differentially expressed genes offers revealing insights into potential molecular regulatory mechanisms employed by TGFß in orchestrating craniofacial ontogeny. [source] Dermal fibroblast-associated gene induction by asiaticoside shown in vitro by DNA microarray analysisBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2004L. Lu Summary Background, Asiaticoside, isolated from Centella asiatica, promotes fibroblast proliferation and extracellular matrix (ECM) synthesis in wound healing. The precise mechanism, however, in molecular and gene expression levels is still unclear. Objective, Using cDNA microarray technology, the alteration of gene expression profiles was determined for human dermal fibroblasts in vitro in the presence of asiaticoside (30 ,g mL,1). Fifty-four genes, with known functions for cell proliferation, cell cycle progression and synthesis of ECM, were significantly upregulated in our ,genome-nest' expression profile at various time points. Furthermore, the mRNA levels and protein production of certain genes responsible for ECM synthesis (e.g. encoding type I and type III collagen proteins) were evaluated by Northern blot and radioimmunoassay, respectively. Results, We found that there is a close correlation between the gene profile, mRNA and protein production in the response of the cells to asiaticoside stimulation. Conclusions, This information could be used for exploring the response of the target genes to asiaticoside in fibroblasts. [source] | ||||||||||