Project description:In this study we used metaproteomics to discern the metabolism and physiology of the microorganisms occurring in the phototrophic mats of four soda lakes in the interior of British Columbia, Canada. Binned and assembled metagenomes were used as the database for protein identification.
Project description:The aim of the study is to evaluate Pit-1-induced genes in the MCF-7 cell line The Pit-1 transcription factor (also known as POU1F1) plays a critical role in cell differentiation during organogenesis of the anterior pituitary in mammals and is a transcriptional activator for pituitary gene transcription. Increased expression of Pit-1 has been reported in human tumorigenic breast cells. Here, we found that Pit-1 overexpression or knockdown in human breast cancer cell lines induced profound phenotypic changes in the expression of proteins involved in cell proliferation, apoptosis, and invasion. In immunodeficient mice, Pit-1 overexpression induced tumoral growth and promoted metastasis in lung. In patients with invasive ductal carcinoma of the breast and node-positive tumors elevated expression of Pit-1 was significantly and independently associated with the occurrence of distant metastasis. These findings suggest that Pit-1 could help to make a more accurate prognosis in patients with node positive breast cancer and may represent a new therapeutic target (Journal of Clinical Investigation 2010, 120:4289-4302)
Project description:The aim of the study is to evaluate Pit-1-induced genes in the MCF-7 cell line The Pit-1 transcription factor (also known as POU1F1) plays a critical role in cell differentiation during organogenesis of the anterior pituitary in mammals and is a transcriptional activator for pituitary gene transcription. Increased expression of Pit-1 has been reported in human tumorigenic breast cells. Here, we found that Pit-1 overexpression or knockdown in human breast cancer cell lines induced profound phenotypic changes in the expression of proteins involved in cell proliferation, apoptosis, and invasion. In immunodeficient mice, Pit-1 overexpression induced tumoral growth and promoted metastasis in lung. In patients with invasive ductal carcinoma of the breast and node-positive tumors elevated expression of Pit-1 was significantly and independently associated with the occurrence of distant metastasis. These findings suggest that Pit-1 could help to make a more accurate prognosis in patients with node positive breast cancer and may represent a new therapeutic target (Journal of Clinical Investigation 2010, 120:4289-4302) MCF-7 cells were transfected with the pcDNA3 (control, two samples as condition, named C1 and C2) or the pcDNA3-Pit-1 overexpression vector (two samples as condition, named 1+ and 2+) for 48 hours.
Project description:Bitter pit is the most important physiological disorder affecting apples. In order to ascertain the genetic bases of its incidence in apple fruit, a mapping population of ‘Braeburn’ (susceptible to bitter pit) × ‘Cameo’ (resistant to bitter pit) cultivars was used to map the trait over two growing seasons. RNA-Seq on pools of RNA extracted from fruits of three resistant and three susceptible to bitter pit progenies at post-fertilization and full maturity stages, permitted us to identify a number of candidate genes underlying genetic resistance/susceptibility to bitter pit.
Project description:This study used an emerging analytical technology (cDNA microarrays) to assess the potential effects of PFC exposure on largemouth bass in TCMA lakes. Microarrays simultaneously measure the expression of thousands of genes in various tissues from organisms exposed to different environmental conditions. From this large data set, biomarkers (i.e., genes that are expressed in response to an exposure to known stressors) and bioindicators (e.g., suites of genes that correspond to changes in organism health) can be simultaneously measured to clarify the relationship between contaminant exposure and organism health. Based on current scientific literature, we hypothesized that gene expression patterns would be altered in fish exposed to PFCs (as compared with fish from reference lakes), and that the magnitude of these changes would correspond to the concentrations of PFCs present throughout TCMA lakes. Patterns of gene expression in largemouth bass observed across the TCMA lakes corresponded closely with PFC concentration. Concentrations of PFCs in largemouth bass varied significantly across the sampled lakes, where the lowest concentrations were found in Steiger and Upper Prior Lakes and the highest concentrations were found in Calhoun and Twin Lakes. Patterns of gene expression were most different (relative to controls) in fish with the highest PFC tissue concentrations, where fish from Twin and Calhoun Lakes were observed to have between 5437 and 5936 differentially expressed genes in liver and gonad tissues. Although gene expression patterns demonstrated a high degree of correlation with PFC concentrations, microarray data also suggest there are likely additional factors influencing gene expression patterns in largemouth bass in TCMA lakes.
Project description:Epigenetic variation has the potential to control environmentally dependent development and contribute to phenotypic responses to local environments. Environmental epigenetic studies of sexual organisms confirm the responsiveness of epigenetic variation, which should be even more important when genetic variation is lacking. A previous study of an asexual snail, Potamopyrgus antipodarum, demonstrated that different populations derived from a single clonal lineage differed in both shell phenotype and methylation signature when comparing lake versus river populations. Here, we examine methylation variation among lakes that differ in environmental disturbance and pollution histories. The differential DNA methylation regions (DMRs) identified among the different lake comparisons suggested a higher number of DMRs and variation between rural Lake 1 and one urban Lake 2 and between the two urban Lakes 2 and 3, but limited variation between the rural Lake 1 and urban Lake 3. DMR genomic characteristics and gene associations were investigated. Observations suggest there is no effect of geographic distance or any consistent pattern of DMRs between urban and rural lakes. Environmental factors may influence epigenetic response.
Project description:Continuous regeneration of digestive enzyme (zymogen) secreting chief cells is a normal aspect of stomach function that is disrupted in pre-cancerous lesions. Regulation of zymogenic cell (ZC) differentiation is poorly understood. Here we profile Parietal, Pit, and Zymogenic cells for comparison and study. Experiment Overall Design: Samples were obtained through Laser-capture microdisection of gastric epithelium. The three samples come from enrichments for Zymogenic Cells (ZC), Parietal Cells (PC), and Mucus Pit Cells (Pit). Experiment Overall Design: Individual parietal cells (visualized by DBA-positivity and autofluorescence) from well-oriented gastric units were dissected (PixCell II LCM apparatus, 7.5-µm spot diameter; CapSure HS LCM caps, Arcturus, Mountain View, CA) one-at-a-time from the pit zone and collected for GeneChips. Pit cells (E-cadherin-positive, DBA-negative) were then collected from the same gastric units. Only the pit cells in a 2-3-cell-thick region at the apex of the gastric unit â?? but not yet upon the gastric surface â?? were taken. ZCs (E-cadherin-positive, GSII/DBA-negative cells in the base zones) were collected from different slides in corpus gastric units after potentially contaminating basal parietal cells had first been dissected and discarded. 3000-5000 individual cells from each cell lineage were isolated from 4-5 individual mice, and RNA was purified by PicoPure kit (Arcturus). RNA integrity was verified, and RNAs for each lineage were pooled from multiple mice and multiple dissections to make 20 ng total RNA, which was then amplified, labeled, and fragmented (by the Arcturus RiboAmp HS kit followed by the RNA Amplification and Labeling Kit from Enzo Life Sciences). The resulting biotinylated cRNA probes were hybridized to Affymetrix (Santa Clara, CA) GeneChip® Mouse Genome 430 2.0 microarrays.