Home About us Contact | |||
mRNA Sequence (mrna + sequence)
Selected AbstractsAberrant splicing of the PTPRD gene mimics microdeletions identified at this locus in neuroblastomasGENES, CHROMOSOMES AND CANCER, Issue 3 2008Prakash Nair Neuroblastoma (NBL), a pediatric tumor arising from precursor cells of the sympathetic nervous system, is characterized by numerous recurrent large-scale chromosomal imbalances. High resolution oligonucleotide array CGH analysis of NBL has previously identified microdeletions that are confined to the 5, UTR of the protein tyrosine phosphatase receptor D (PTPRD) gene, implicating this gene in the pathogenesis of these tumors. Here, we demonstrate that the 5, UTR of this gene, consisting of 11 noncoding exons, is also aberrantly spliced in >50% of NBL primary tumors and cell lines. The loss of exons from the 5, UTR region through aberrant splicing results in aberrant mRNA isoforms that are similar to those generated through microdeletions. The aberrant splicing or microdeletion of 5, UTR exons in such a high proportion of tumors indicates that loss of these exons dys-regulates the mRNA sequence. To further validate the role of PTPRD in NBL, we have examined the expression of this gene in normal fetal adrenal neuroblasts (the cell of origin of NBL) and in tumors from patients with either low stage or high stage disease. This gene is expressed at lower levels in high stage NBL tumors, particularly those with amplification of MYCN, relative to low stage tumors or normal fetal adrenal neuroblasts, consistent with the possibility that loss of the 5, UTR exons have destabilized the mRNA. © 2007 Wiley-Liss, Inc. [source] Evaluation of SPATA1 -associated markers for stallion fertilityANIMAL GENETICS, Issue 4 2009K. Giesecke Summary Stallion fertility is an economically important trait because the use of artificial insemination is increasing in the horse industry and superior sires are used more intensely. Molecular genetic markers may be useful as early indicators for a stallion's fertility and genetic improvement programmes. The testis-specific SPATA1 protein is involved in shaping the sperm head during spermatogenesis. Thus, the spermatogenesis associated 1 (SPATA1) gene was chosen as candidate for stallion fertility, and we analysed intragenic single nucleotide polymorphisms (SNPs) as genetic markers for the least square means (LSM) of the pregnancy rate per oestrus of stallions and breeding values (BV) for the paternal and embryonic component of the pregnancy rate per oestrus. We sequenced the cDNA of SPATA1 to verify the annotated mRNA sequence. One SPATA1 -associated intronic SNP (BIEC2-968854) showed a significant association with the embryonic component of BVs of stallions for the pregnancy rate per oestrus. The embryonic component of BVs was positively associated with homozygous C/C stallions. Both the additive and dominance effects were significant with values of ,5.8% (P = 0.01) and ,6.4% (P = 0.02) for the embryonic component of BVs. For the same SNP, a suggestive association was found for the LSM of the pregnancy rate per oestrus of stallions. Heterozygous stallions had higher pregnancy rates per oestrus than homozygous stallions. The dominance effect was 4.1% with a nominal P -value of 0.02. The SNP BIEC2-968854 can change an SP1 binding site and thus we assume that gene regulation may be influenced through this intronic mutation. This is the first report on SPATA1 being associated with the pregnancy rate per oestrus for stallions. [source] Substrate recognition of type III secretion machines ,testing the RNA signal hypothesisCELLULAR MICROBIOLOGY, Issue 9 2005Joseph A. Sorg Summary Secretion by the type III pathway of Gram-negative microbes transports polypeptides into the extracellular medium or into the cytoplasm of host cells during infection. In pathogenic Yersinia spp., type III machines recognize 14 different Yop protein substrates via discrete signals genetically encoded in 7,15 codons at the 5, portion of yop genes. Although the signals necessary and sufficient for substrate recognition of Yop proteins have been mapped, a clear mechanism on how proteins are recognized by the machinery and then initiated into the transport pathway has not yet emerged. As synonymous substitutions, mutations that alter mRNA sequence but not codon specificity, affect the function of some secretion signals, recent work with several different microbes tested the hypothesis of an RNA-encoded secretion signal for polypeptides that travel the type III pathway. This review summarizes experimental observations and mechanistic models for substrate recognition in this field. [source] Using DNA sequencing electrophoresis compression artifacts as reporters of stable mRNA structures affecting gene expressionELECTROPHORESIS, Issue 21 2007Divya Kapoor Abstract The formation of secondary structure in oligonucleotide DNA is known to lead to "compression" artifacts in electropherograms produced through DNA sequencing. Separately, the formation of secondary structure in mRNA is known to suppress translation; in particular, when such structures form in a region covered by the ribosome either during, or shortly after, initiation of translation. Here, we demonstrate how a DNA sequencing compression artifact provides important clues to the location(s) of translation-suppressing secondary structural elements in mRNA. Our study involves an engineered version of a gene sourced from Rhodothermus marinus encoding an enzyme called Cel12A. We introduced this gene into Escherichia coli with the intention of overexpressing it, but found that it expressed extremely poorly. Intriguingly, the gene displayed a remarkable compression artifact during DNA sequencing electrophoresis. Selected "designer" silent mutations destroyed the artifact. They also simultaneously greatly enhanced the expression of the cel12A gene, presumably by destroying stable mRNA structures that otherwise suppress translation. We propose that this method of finding problem mRNA sequences is superior to software-based analyses, especially if combined with low-temperature CE. [source] Immunological Detection of in Vitro Formed Phosphatidylethanol,An Alcohol Biomarker,With Monoclonal AntibodiesALCOHOLISM, Issue 6 2008Antti E. Nissinen Background:, Phosphatidylethanol (PEth) is a promising new marker for detecting long-term alcohol abuse with excellent sensitivity and specificity. Current methods are based on the high performance liquid chromatography,mass spectrometric method and therefore require high levels of expertise and expensive instrumentation. This study was designed to generate PEth-specific monoclonal antibodies for PEth immunoassay development. Methods:, C57/BL6 mice were immunized with PEth in 3 different carriers, mouse serum albumin, mouse high-density lipoproteins, and human low-density lipoprotein (LDL). Mouse splenocytes were fused with a mouse myeloma cell line using the hybridoma technique. Mouse IgM-producing cell lines were selected by limiting dilutions. Binding characteristics of the anti-PEth antibodies were studied using luminometric immunoassays and sequence analysis of the variable region mRNA sequences of the antibodies. Produced antibodies were purified by chromatographic methods. PEth was detected with these antibodies in fluorescence immunoassay and flow cytometric analysis. Results:, We generated monoclonal cell lines (2B1 and 2E9) that produce IgM antibodies binding specifically to PEth but not to structurally or chemically similar phospholipids, such as phosphatidylcholine, phosphatidic acid, and cardiolipin. We show here that these anti-PEth antibodies can be used to detect PEth in a fluorescent PEth assay and FACS analysis of human red blood cell samples spiked with PEth. Conclusions:, The present study shows that PEth-specific monoclonal antibodies can be generated using traditional hybridoma technique. Immunogenicity of PEth was enhanced using human LDL as an immunization carrier. The generated monoclonal anti-PEth antibodies, 2B1 and 2E9 bind to PEth in fluid phase and in biological membranes. [source] Identifications of expressed sequence tags from Pacific threadfin (Polydactylus sexfilis) skeletal muscle cDNA libraryAQUACULTURE RESEARCH, Issue 4 2010Shizu Watanabe Abstract Pacific threadfin (Polydactylus sexfilis), locally known as Moi, is a desirable fish for aquaculture and recreational fishing. To understand the basic mechanism of muscle formation and its impacts on flesh quality, we established a cDNA library using mRNA of the skeletal muscle tissue from fingerlings. The library size was 1.1 × 108 plaque forming units mg,1 and the percentage of recombinant clones was >81%. A pilot sequencing project from 181 clones identified 129 useful expressed sequence tags (ESTs), of which 90 ESTs exhibited significant homology to known genes and 39 ESTs have low homologies to unknown genes by blast algorithm. The most abundant EST from the pilot sequence data is nikotinamide riboside kinase 2 (59 times), followed by 60S ribosomal protein L24 (12 times) and ribosomal protein L8 (5 times). Fourteen novel genes were retrieved from the sequenced clones and subjected to gene ontology annotation. Four mRNA sequences were identified as significant regulators of transcription, including Not2p, Tsc22 domain family 2, LIM domain binding factor 3 and mesenchyme homeobox 2. These results suggest that the muscle cDNA library is an useful source for identifying EST sequences of Pacific threadfin. [source] |