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mRNA Species (mrna + species)
Selected AbstractsA transcriptome analysis of isoamyl alcohol-induced filamentation in yeast reveals a novel role for Gre2p as isovaleraldehyde reductaseFEMS YEAST RESEARCH, Issue 1 2007Michael Hauser Abstract A transcriptome analysis was performed of Saccharomyces cerevisiae undergoing isoamyl alcohol-induced filament formation. In the crucial first 5 h of this process, only four mRNA species displayed strong and statistically significant increases in their levels of more than 10-fold. Two of these (YEL071w/DLD3 and YOL151w/GRE2) appear to play important roles in filamentation. The biochemical activities ascribed to these two genes (d -lactate dehydrogenase and methylglyoxal reductase, respectively) displayed similarly timed increases to those of their respective mRNAs. Mutants carrying dld3 mutations displayed reduced filamentation in 0.5% isoamyl alcohol and needed a higher concentration of isoamyl alcohol to effect more complete filament formation. Hence, DLD3 seems to be required for a full response to isoamyl alcohol, but is not absolutely essential for it. Mutants carrying gre2 mutations were derepressed for filament formation and formed large, invasive filaments even in the absence of isoamyl alcohol. These results indicate a previously unsuspected and novel role for the GRE2 gene product as a suppressor of filamentation by virtue of encoding isovaleraldehyde reductase activity. [source] Transcription of major histocompatibility complex class I (Kb) and transporter associated with antigen processing 1 and 2 genes is up-regulated with ageIMMUNOLOGY, Issue 3 2004Alain G. Assounga Summary The transporter associated with antigen processing 1 and 2 (TAP1 and TAP2) genes belong to the ATP-binding cassette family of transporter genes. They provide peptides necessary for the assembly of major histocompatibility complex (MHC) class I molecules by transporting these peptides into the endoplasmic reticulum. As MHC class I protein expression increases with age, we have explored the effect of age on the transcription of MHC class I genes (Kb) and TAP1 and TAP2 genes in C57BL/6 mice. Blood and spleen lymphocytes were isolated from mice aged from 3 months to over 24 months. RNA was extracted and mRNA for Kb, TAP1, TAP2 was quantified using slot-blot hybridization followed by densitometry. There was a parallel age-related increase (1·5-fold) in blood lymphocyte mRNA of these genes from 3 months to 21 months. In mice over 24 months old there was a decrease in Kb and TAP1 mRNA, but an increase in TAP2 mRNA. In spleen lymphocytes an age-related increase in all three mRNA species occurred throughout life. While MHC class I and Tap genes underwent very similar age-related changes, MHC class I mRNA was about 50 times more abundant than either TAP1 or TAP2 mRNA. [source] Specific interaction between Sam68 and neuronal mRNAs: Implication for the activity-dependent biosynthesis of elongation factor eEF1AJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2009Julien Grange Abstract In cultured hippocampal neurons and in adult brain, the splicing regulatory protein Sam68 is partially relocated to the somatodendritic domain and associates with dendritic polysomes. Transfer to the dendrites is activity-dependent. We have investigated the repertoire of neuronal mRNAs to which Sam68 binds in vivo. By using coimmunoprecipitation and microarray screening techniques, Sam68 was found to associate with a number of plasticity-related mRNA species, including Eef1a1, an activity-responsive mRNA coding for translation elongation factor eEF1A. In cortical neuronal cultures, translation of the Eef1a1 mRNA was strongly induced by neuronal depolarisation and correlated with enhanced association of Sam68 with polysomal mRNAs. The possible function of Sam68 in Eef1a1 mRNA utilization was studied by expressing a dominant-negative, cytoplasmic Sam68 mutant (GFP-Sam68,C) in cultured hippocampal neurons. The level of eEF1A was lower in neurons expressing GFP-Sam68,C than in control neurons, supporting the proposal that endogenous Sam68 may contribute to the translational efficiency of the Eef1a1 mRNA. These findings are discussed in the light of the complex, potentially crucial regulation of eEF1A biosynthesis during long-term synaptic change. © 2008 Wiley-Liss, Inc. [source] Gene expression in chorionic villous samples at 11 weeks' gestation from women destined to develop preeclampsiaPRENATAL DIAGNOSIS, Issue 10 2008Antonio Farina Abstract Objective To evaluate the direct alterations in mRNA expression among chorionic villous samples from 11 weeks' pregnant women who would develop preeclampsia (PE) later in the pregnancy. Method Case-control study encompassing five women destined to develop PE [cases matched 1:5 for gestational age (GA) with 25 controls]. We quantified mRNA expression on tissue samples from chorionic villous sampling (CVS) of normal and PE patients. We then assessed mRNA expressions of vascular endothelial growth factor (VEGFA), VEGFA receptor 1 (Flt-1), endoglin (Eng), placental growth factor (PlGF), transforming growth factor-,1 (TGF-,1), heme oxygenase-1 (HO-1) and superoxide dismutase (SOD). Data were analyzed by nonparametric rank analysis. Results For all the mRNA species considered in this study, all the mean observed ranks in the PE group were significantly altered compared to the rank expectation among controls. mRNA for Eng and TGF-,1 were the markers with the highest degree of aberration in PE, in respect to controls. The results are consistent with those already reported for the corresponding circulating proteins. mRNA for HO-1 and SOD were instead associated with the lowest aberration. Conclusion It is assumed that the pathogenesis of PE is associated with pathophysiological alterations to trophoblasts in early gestation. Our study has directly proved that gene expressions relating to angiogenesis or oxidative stress are altered in the first trimester trophoblasts that go on to develop PE later. These results would put the basis for a possible screening method for PE by using residual CVS. Copyright © 2008 John Wiley & Sons, Ltd. [source] mRNA Encoding a Putative RNA Helicase of the DEAD-Box Gene Family is Up-Regulated in Trypomastigotes of Trypanosoma cruziTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 6 2000ALBERTO M. DÍAZ AÑEL ABSTRACT. Differential display of mRNAs from Trypanosoma cruzi epimastigote and metacyclic trypomastigote stages showed several mRNA species differing in their expression level. The cDNA corresponding to one of these mRNAs was used as a probe in Northern blots and identified a RNA product of 2.6 kb with an expression level eight or more times higher in trypomastigotes than in epimastigotes. This probe was also used to screen a genomic library of T. cruzi CL Brener clone prepared in lambda FIX. A clone of about 15 kb was selected that, after partial sequencing, revealed an open reading frame of 688 amino acids encoding a deduced protein with similarity to RNA helicases of the DEAD-box gene family. The presence of the eight conserved motifs characteristic of the DEAD protein family was observed in the T. cruzi sequence, indicating that it corresponds to a putative RNA helicase gene, which we named HelTc. Southern blot analysis indicated that HelTc is a single-copy gene. Pulsed-field gel electrophoresis separation of chromosomes of several isolates of T. cruzi showed that this gene was localized in one or two chromosomal bands. [source] | ||||||||||