Search results for "messenger"
showing 10 items of 1493 documents
Anything but Ordinary - Emerging Splicing Mechanisms in Eukaryotic Gene Regulation.
2021
Splicing of precursor mRNAs (pre-mRNA) is an important step during eukaryotic gene expression. The identification of the actual splice sites and the proper removal of introns are essential for the production of the desired mRNA isoforms and their encoded proteins. While the basic mechanisms of splicing regulation are well understood, recent work has uncovered a growing number of noncanonical splicing mechanisms that play key roles in the regulation of gene expression. In this review, we summarize the current principles of splicing regulation, including the impact of cis and trans regulatory elements, as well as the influence of chromatin structure, transcription, and RNA modifications. We f…
Competing endogenous RNA and interactome bioinformatic analyses on human telomerase.
2014
We present a classic interactome bioinformatic analysis and a study on competing endogenous (ce) RNAs for hTERT. The hTERT gene codes for the catalytic subunit and limiting component of the human telomerase complex. Human telomerase reverse transcriptase (hTERT) is essential for the integrity of telomeres. Telomere dysfunctions have been widely reported to be involved in aging, cancer, and cellular senescence. The hTERT gene network has been analyzed using the BioGRID interaction database (http://thebiogrid.org/) and related analysis tools such as Osprey (http://biodata.mshri.on.ca/osprey/servlet/Index) and GeneMANIA (http://genemania.org/). The network of interaction of hTERT transcripts h…
Complex Contribution of the 3′-Untranslated Region to the Expressional Regulation of the Human Inducible Nitric-oxide Synthase Gene
2000
Cytokine stimulation of human DLD-1 cells resulted in a marked expression of nitric-oxide synthase (NOS) II mRNA and protein accompanied by only a moderate increase in transcriptional activity. Also, there was a basal transcription of the NOS II gene, which did not result in measurable NOS II expression. The 3′-untranslated region (3′-UTR) of the NOS II mRNA contains four AUUUA motifs and one AUUUUA motif, known to destabilize the mRNAs of proto-oncogenes, nuclear transcription factors, and cytokines. Luciferase reporter gene constructs containing the NOS II 3′-UTR showed a significantly reduced luciferase activity. The embryonic lethal abnormal vision (ELAV)-like protein HuR was found to b…
The transcriptional inhibitor thiolutin blocks mRNA degradation in yeast.
2007
Thiolutin is commonly used as a general inhibitor of transcription in yeast. It has been used to calculate mRNA decay rates by stopping the transcription and then determining the relative abundance of individual mRNAs at different times after inhibition. We report here that thiolutin is also an inhibitor of mRNA degradation, and thus its use can lead to miscalculations of mRNA half-lives. The inhibition of mRNA decay seems to affect the mRNA degradation pathway without impeding poly(A) shortening, given that the decay rate of total poly(A) amount is not reduced by thiolutin. Moreover, the thiolutin-dependent inhibition of mRNA degradation has variable effects on different functional groups …
Genomic-Wide Methods to Evaluate Transcription Rates in Yeast
2011
Gene transcription is a dynamic process in which the desired amount of an mRNA is obtained by the equilibrium between its transcription (TR) and degradation (DR) rates. The control mechanism at the RNA polymerase level primarily causes changes in TR. Despite their importance, TRs have been rarely measured. In the yeast Saccharomyces cerevisiae, we have implemented two techniques to evaluate TRs: run-on and chromatin immunoprecipitation of RNA polymerase II. These techniques allow the discrimination of the relative importance of TR and DR in gene regulation for the first time in a eukaryote.
Messenger RNA degradation is initiated at the 5′ end and follows sequence- and condition-dependent modes in chloroplasts
2011
Using reporter gene constructs, consisting of the bacterial uidA (GUS) coding region flanked by the 5' and 3' regions of the Chlamydomonas rbcL and psaB genes, respectively, we studied the degradation of mRNAs in the chloroplast of Chlamydomonas reinhardtii in vivo. Extending the 5' terminus of transcripts of the reporter gene by more than 6 nucleotides triggered rapid degradation. Placing a poly(G) tract, known to pause exoribonucleases, in various positions downstream of the 5' terminus blocked rapid degradation of the transcripts. In all these cases the 5' ends of the accumulating GUS transcripts were found to be trimmed to the 5' end of the poly(G) tracts indicating that a 5' → 3' exori…
Early stress response of human nasal respiratory epithelia after exposure to 1-methoxypropanol-2
2007
To evaluate the impact of 1-methoxypropanol-2 (MEP) for the stimulation of an inflammatory response in human respiratory mucosa, we exposed 22 primary cell cultures of nasal respiratory epithelia of healthy individuals to MEP concentrations at the level of the German MAK-value (100 ppm) and to the 10-fold concentration (1000 ppm). After 4 and 24h we analyzed the transcription of TNF-alpha, IL-1beta, IL-6, IL-8, MCP-1, GMCSF, Cox-1 and Cox-2 by quantitative PCR as well as the release of the respective cytokines by ELISA. At both MEP concentrations we observed a significant increase of TNF-alpha-, IL-1beta-, IL-6- and Cox-2-transcripts after 4h. After 24h cytokine transcription of TNF-alpha, …
The four murine peroxisomal ABC-transporter genes differ in constitutive, inducible and developmental expression.
1999
Four ATP-binding cassette (ABC) half-transporters have been identified in mammalian peroxisomes: adrenoleukodystrophy protein (ALDP), adrenoleukodystrophy-related protein (ALDRP), 70-kDa peroxisomal membrane protein (PMP70) and PMP70-related protein (P70R). Inherited defects in ALDP cause the neurodegenerative disorder X-linked adrenoleukodystrophy (X-ALD). By comparative Northern blot analyses we found each of the four murine peroxisomal ABC transporter mRNA species at maximum abundance only in a few tissues, which differed for each family member. The four genes were also regulated differentially during mouse brain development: ALDP mRNA was most abundant in embryonic brain and gradually d…
Cloning of a novel putative G-protein-coupled receptor (NLR) which is expressed in neuronal and lymphatic tissue.
1993
AbstractA novel G-protein-coupled receptor was isolated from mouse and rat neuronal and lymphatic tissues. The amino acid sequence of the rat receptor (rNLR) shows an overall homology of 80% to a recently cloned receptor from Burkitt's lymphoma cells (BLR1) which is exclusively expressed in lymphatic tissues [(1992) Eur. J. Immunol. 22, 2795]. Much less homology between rNLR and BLR1 was observed at the N-terminus (about 40%), whereas rNLR and the mouse homologue mNLR show 92% amino acid identity. Northern blot analysis of NLR revealed a predominant 5.5 kb mRNA species in various brain regions and neuronal cell lines, whereas in the spleen a 3 kb transcript is predominant. This distribution…
Molecular genetics of autosomal dominant retinitis pigmentosa (ADRP): a comprehensive study of 43 Italian families
2005
Retinitis pigmentosa is the most common form of retinal degeneration and is heterogeneous both clinically and genetically. The autosomal dominant forms ( ADRP) can be caused by mutations in 12 different genes. This report describes the first simultaneous mutation analysis of all the known ADRP genes in the same population, represented by 43 Italian families. This analysis allowed the identification of causative mutations in 12 of the families (28% of the total). Seven different mutations were identified, two of which are novel (458delC and 6901C --> T (P2301S), in the CRX and PRPF8 genes, respectively). Several novel polymorphisms leading to amino acid changes in the FSCN2, NRL, IMPDH1, and…