Project description:Background: Standard Guthrie cards have been widely used to collect blood samples from neonates for newborn screening programs, and to a lesser extent, from normal controls and patients in research studies. Ease of blood collection (small quantity and less pain), transportation, and storage are the advantages of using these cards. It is believed that RNA obtained from these samples is of low quantity and degraded quality. However, we recently discovered that approximately 3,500 expressed genes can be detected from blood spot samples using in-house made, low resolution cDNA microarrays. Here, we established a new and improved methodology to acquire gene expression profiles from blood spot cards using commercially-available high resolution microarrays. We determined the optimal number of blood spot punches required for maximal RNA extraction, eliminated uses of trizol and chloroform for RNA extraction by using a modified protocol of the illustra Mini Spin Kit from GE-Whatm an, concentrated the quantity of RNA templates before amplification, improved amplification efficiency using the new Ribo-SPIA technology in WT-Ovation Pico System (WT-Pico) by NuGEN, before the samples were hybridized onto 4x44K whole human genome gene expression microarrays from Agilent. Nine dried blood spot samples were collected from a control population and stored at ~ -80 °C between 6 months to 2 years. High quality RNA was extracted from the buffy coat of the same individuals as a reference and processed using the standard Agilent microarray procedure. Commercially-available brain RNA was used as a positive control in both standard and new procedures for microarrays. Results: Three 3-mm punches produced the highest yield of total RNA using the non-trizol extraction method. Three to six nanogram per microliter of RNA can be concentrated and is sufficient to be amplified using the WT-Pico. Approximately 9,000 expressed genes can be detected after normalization and background correction of the microarray data. Conclusion: Genome-wide gene expression profile can be obtained from archived dried blood spot samples. Our new and improved methodology will add value to the perception of utilizing archival Guthrie cards eg. neonatal blood spot cards as unique biospecimens for molecular genomics and diagnostic studies of perinatal diseases such as pediatric cancers. Keywords: Gene Expression experiment Archival guthrie blood-spot cards may contain valuable data for epidemiological or other studies. Showing microarray data from guthrie blood-spot cards
Project description:Background: Standard Guthrie cards have been widely used to collect blood samples from neonates for newborn screening programs, and to a lesser extent, from normal controls and patients in research studies. Ease of blood collection (small quantity and less pain), transportation, and storage are the advantages of using these cards. It is believed that RNA obtained from these samples is of low quantity and degraded quality. However, we recently discovered that approximately 3,500 expressed genes can be detected from blood spot samples using in-house made, low resolution cDNA microarrays. Here, we established a new and improved methodology to acquire gene expression profiles from blood spot cards using commercially-available high resolution microarrays. We determined the optimal number of blood spot punches required for maximal RNA extraction, eliminated uses of trizol and chloroform for RNA extraction by using a modified protocol of the illustra Mini Spin Kit from GE-Whatm an, concentrated the quantity of RNA templates before amplification, improved amplification efficiency using the new Ribo-SPIA technology in WT-Ovation Pico System (WT-Pico) by NuGEN, before the samples were hybridized onto 4x44K whole human genome gene expression microarrays from Agilent. Nine dried blood spot samples were collected from a control population and stored at ~ -80 °C between 6 months to 2 years. High quality RNA was extracted from the buffy coat of the same individuals as a reference and processed using the standard Agilent microarray procedure. Commercially-available brain RNA was used as a positive control in both standard and new procedures for microarrays. Results: Three 3-mm punches produced the highest yield of total RNA using the non-trizol extraction method. Three to six nanogram per microliter of RNA can be concentrated and is sufficient to be amplified using the WT-Pico. Approximately 9,000 expressed genes can be detected after normalization and background correction of the microarray data. Conclusion: Genome-wide gene expression profile can be obtained from archived dried blood spot samples. Our new and improved methodology will add value to the perception of utilizing archival Guthrie cards eg. neonatal blood spot cards as unique biospecimens for molecular genomics and diagnostic studies of perinatal diseases such as pediatric cancers. Keywords: Gene Expression experiment
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Homo sapiens fresh whole blood was infected with Candida tropicalis. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Measurement of Candida tropicalis gene expression.
Project description:Homo sapiens fresh whole blood was infected with Candida parapsilosis. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Measurement of Homo sapiens gene expression.
Project description:Homo sapiens fresh whole blood was infected with Candida glabrata. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Measurement of Candida glabrata gene expression.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:We investigated the effect of antenatal corticosteroid exposure (ACS) on the DNA methylation patterns in the whole blood of female guinea pig offspring. Guinea pig dams were treated with saline or betamethasone on gestational days 50/51. Whole blood was collected from newborn offspring (post-natal day 1) and dried on blood spot cards. Methylation assessment using genomic DNA was performed with reduced representation bisulfite sequencing techniques.