Search results for "mRNA"

ROLE OF RNA BINDING PROTEIN IN THE NERVE CELL DIFFERENTIATION

2014

Synthesis of H1˚ and H3.3 histone proteins, in the developing rat brain, seems to be regulated mainly at the post-transcriptional level. Since regulation of RNA metabolism depends on a series of RNA-binding proteins (RBPs), we have been searching for RBPs involved in the post-transcriptional regulation of the H1˚ and H3.3 genes. Previously, we reported isolation, from a cDNA expression library, of an insert encoding a novel protein, the C-terminal half of which is identical to that of PEP-19, a brain-specific protein involved in calcium metabolism. The novel protein was called long PEP-19 isoform (LPI). We showed that LPI, as well as PEP-19, can bind H1˚ RNA. Since PEP19 and LPI contain a c…

Using mRNA and small RNA gene expression changes in peripheral blood for easy detection of Ra-223 incorporation

2019

The mRNA degradation factor Xrn1 regulates transcription elongation in parallel to Ccr4

2019

Abstract Co-transcriptional imprinting of mRNA by Rpb4 and Rpb7 subunits of RNA polymerase II (RNAPII) and by the Ccr4–Not complex conditions its post-transcriptional fate. In turn, mRNA degradation factors like Xrn1 are able to influence RNAPII-dependent transcription, making a feedback loop that contributes to mRNA homeostasis. In this work, we have used repressible yeast GAL genes to perform accurate measurements of transcription and mRNA degradation in a set of mutants. This genetic analysis uncovered a link from mRNA decay to transcription elongation. We combined this experimental approach with computational multi-agent modelling and tested different possibilities of Xrn1 and Ccr4 acti…

The total mRNA concentration buffering system in yeast is global rather than gene-specific

2021

Gene expression in eukaryotes does not follow a linear process from transcription to translation and mRNA degradation. Instead it follows a circular process in which cytoplasmic mRNA decay crosstalks with nuclear transcription. In many instances, this crosstalk contributes to buffer mRNA at a roughly constant concentration. Whether the mRNA buffering concept operates on the total mRNA concentration or at the gene-specific level, and if the mechanism to do so is a global or a specific one, remain unknown. Here we assessed changes in mRNA concentrations and their synthesis rates along the transcriptome of aneuploid strains of the yeast Saccharomyces cerevisiae. We also assessed mRNA concentra…

Cancer cells can affect behaviour of neighbouring cells by transferring molecules through extracellular vesicles

2017

Most cells release into the extracellular space membrane-bound structures of different sizes, origin and composition, collectively called extracellular vesicles (EVs) [1]. Tumor cells are much more active than normal cells in producing EVs. Because of this property, they are able to transfer both nucleic acids and proteins to the surrounding normal cells, thus inducing in these latter at least some transformed behavior. We previously showed that EVs produced by G26/24 oligodendroglioma cells can horizontally transfer to their neighbours radioactive proteins [2]. In addition, EVs released by these cells contain pro-apoptotic proteins, such as TRAIL and Fas-Ligand, able to induce apoptosis in…

RNA as a carrier of epigenetic information

2017

Both prokaryotic and eukaryotic cells release into the extracellular matrix membrane-bound structures of different sizes, origin and composition, collectively called extracellular vesicles (EVs) [1]. Tumor cells, in particular, use EVs to transfer both nucleic acids and proteins to the surrounding normal cells, thus inducing in them transformed behaviours or killing them. G26/24 oligodendroglioma cells, for example, transfer by EVs pro-apoptotic proteins, such as TRAIL and Fas-Ligand [2], extracellular matrix remodelling proteases (such as ADAMTS) [3], and even the H1.0 histone protein [4]. Another tumour cell line, with a different tissue origin (A375 melanoma cells) releases into the medi…

Identification of a prognostic gene signature associated with MBP-1 expression in ErbB2-negative breast carcinomas

2014

The ENO1 transcript, which encodes the glycolitic enzyme alpha-enolase, can be translated into a shorter nuclear protein called Myc-promoter Binding Protein-1 (MBP-1) by using an alternative translation start site. MBP-1 acts as a negative regulator of c-Myc, ErbB2 and Cox2 genes (1). Several evidences indicate that MBP-1 acts as a tumor suppressor in breast carcinoma and prostate cancer and its expression results in a reduced invasive ability (2). In our previous studies, we showed that MBP-1 is expressed and easily detectable in normal breast epithelial cells, but a loss of expression occurs in most primary invasive ductal carcinomas (IDC) of the breast. Furthermore, in these tumors MBP-1…

RNA quality control: RppH activity allows selective removal of nonsense messages in E. coli.

2009

Polar effect, the reduced expression level of sequences downstream to mutations reducing translation efficiency, is usually due to transcription termination or inefficient translation reinitiation. Untranslated mRNAs are known to be quickly degraded, probably because of their increased accessibility to degradative enzymes due to the absence of translating ribosomes. In III-VI-I operon of phage f1, a strong polar effect is observed in a gIII 5’ proximal nonsense mutant, resulting in a very fast, RNaseE mediated, degradation of any full-length mRNA. RNaseE is a key component of the E. coli degradosome, the major RNA processing/degrading machinery. Its endonucleolytic activity is strongly enha…

Investigating CRISPR-CAS13b as a tool for the RNA editing of CFTR mRNA with premature stop codon

2020

Background and Rationale Some CF patients are compound heterozygous or homozygous for nonsense mutations in the CFTR gene. Mutant CFTR gene coding for transcripts with premature termination codons (PTCs) is responsible for truncated CFTR protein and for a severe form of the disease. In a precision medicine framework the “REPAIRv2” (RNA Editing for Programmable A to I Replacement v2) tool, developed in the laboratory of Dr. Feng Zhang (USA), seems a good alternative to restore the full-length CFTR protein by editing its mRNA containing PTCs. This new approach is based on the possibility of targeting a deaminase enzyme (huADAR2) to a specific Adenosine, to be edited to Inosine (G analogue), o…

Dal trascrittoma all’interattoma di miRNA: identificazione sperimentale e bioinformatica delle interazioni funzionali miRNA:mRNA

2013

I miRNA, piccole molecole endogene di RNA non codificante, regolano l’espressione genica attraverso la degradazione dei messaggeri (mRNA) o l’inibizione della traduzione. I miRNA maturi interagiscono con le proteine del complesso RISC (RNA-induced silencing complex) tra cui le proteine Argonaute (Ago), capaci di legare direttamente i miRNA e di mediare la regolazione dell’espressione genica in seguito alla interazione del miRNA con il proprio mRNA target. Un singolo miRNA può legare diversi mRNA e ciascun mRNA può essere regolato da diversi miRNA. La maggior parte dei software di predizione oggi disponibili individuano i putativi target di singoli miRNA ignorando caratteristiche di tipo glo…