RNA binding proteins: putative regulative role in mitochondrial proteins expression.

Mitochondrial protein expression in Ratt and in human cells

In the present paper, we analyzed some aspects of the post-transcriptional regulation of two COX (cy-tochrome c oxidase) subunits, i.e. mitochondrion-encoded COXIII and nucleus-encoded COXIV. In particular, by T1 RNase protection assays, we found two proteins, present in mitochondrial extracts from adult rat brain and testis, able to bind COXIII mRNA. We also found cytoplasmic proteins present in testis, kidney and heart extracts that bind COXIV mRNA. Moreover, to study the expression of mitochondrial proteins in tumor cells, we quantitated COXIV and Hsp60 chaperonin abundance in two epithelial cell lines from human breast, one neoplastic (MDA-MB231) and the other immortalized and non-tumor…

Mitochondrial proteins regulation in Rattus norvegicus and human cells

Effects of cadmium chloride on some mitochondria-related activity and gene expression of human MDA-MB231 breast tumor cells.

It was reported that cadmium is able to exert a cytotoxic effect on tumor MDA-MB231 cells, which shows signs of "non-classical" apoptosis and is characterized by drastic changes in gene expression pattern. In this study, we have extended our knowledge of metal-breast cancer cell interactions by analyzing some mitochondria-related aspects of the stress response to CdCl(2) at either 5 or 50 microM 24- or 96-h exposure, by cytochemical, conventional PCR and Northern/Western blot techniques. We demonstrated that (i) no modification of the mitochondrial mass was detectable due to CdCl(2) exposure; (ii) the respiration activity appeared to be increased after 96-h exposures, while the production o…

Mitochondrial compartment: a possible target of cadmium effects on breast epithelial cells.

Cadmium–breast epithelial cell interactions were studied by analyzing some mitochondria-related aspects of stress response. We treated immortalized non-tumor breast cells with 5 or 50 μM CdCl2 for 24 or 96 h demonstrating that the exposure did not cause a significant mitochondrial proliferation, while it induced a significant increase in the respiratory activity and mitochondrial polarization. In addition, we found that hsp60 was up-regulated while hsp70 and COXII and COXIV were down-regulated. The mRNA for hsp70 remained constant and only the inducible form of the 70-kDa heat shock protein was over expressed. The mRNAs for COXII and COXIV remained constant after 24 h and increased after lo…

Possible mechanisms regulating the expression of nuclear and mitochondrial genes

Cytochemical and molecular analyses on mitochondria of immortalized and neoplastic epithelial cells of the human breast after cadmium treatments

Possible mechanisms regulating the expression of nuclear and mitochondrial genes

Nuclear-mitochondrial interaction.

The biogenesis of mitochondria depends on the coordinated expression of nuclear and mitochondrial genomes. Consequently, the control of mitochondrial biogenesis and function depends on extremely complex processes requiring a variety of well orchestrated regulatory mechanisms. It is clear that the interplay of transcription factors and coactivators contributes to the expression of both nuclear and mitochondrial respiratory genes. In addition, the regulation of mitochondria biogenesis depends on proteins that, interacting with messenger RNAs for mitochondrial proteins, influence their metabolism and expression. Moreover, a tight regulation of the import and final assembly of mitochondrial pro…

Mitochondrial protein expression in rattus norvegicus and human cells.

Effect of cadmium chloride on some mitochondria-related activity and gene expression of human MDA-MB231 breast tumor cells

Regolazione dell’espressione delle subunità III e IV della citocromo c ossidasi

Cadmium and mitochondria

The heavy metal cadmium (Cd) a pollutant associated with several modern industrial processes, is absorbed in significant quantities from cigarette smoke, water, food and air contaminations. It is known to have numerous undesirable effects on health in both experimental animals and humans, targeting kidney, liver and vascular system. The molecular mechanism accounting for most of the biological effects of Cd are not well-understood and the toxicity targets are largely unidentified. The present review focuses on important recent advances about the effects of cadmium on mitochondria of mammalian cells. Mitochondria are the proverbial powerhouses of the cell, running the fundamental biochemical…

Correction: DAPIT Over-Expression Modulates Glucose Metabolism and Cell Behaviour in HEK293T Cells

Introduction Diabetes Associated Protein in Insulin-sensitive Tissues (DAPIT) is a subunit of mitochondrial ATP synthase and has also been found to associate with the vacuolar H+-ATPase. Its expression is particularly high in cells with elevated aerobic metabolism and in epithelial cells that actively transport nutrients and ions. Deletion of DAPIT is known to induce loss of mitochondrial ATP synthase but the effects of its over-expression are obscure. Results In order to study the consequences of high expression of DAPIT, we constructed a transgenic cell line that constitutively expressed DAPIT in human embryonal kidney cells, HEK293T. Enhanced DAPIT expression decreased mtDNA content and …

Proteine di fusione, metodo di preparazione, e relativi anticorpi per la diagnosi di patologie mitocondriali

Proteins participating to the post-transcriptional regulation of the mitochondrial cytochrome c oxidase subunit IV via elements located in the 3′UTR

Abstract In developing rat brain cytochrome c oxidase subunit IV (COXIV) expression is also regulated at post-transcriptional level and two 3′UTR-COXIV RNA-binding factors have been identified. Here, we report the enrichment and identification of the factors from just born rat brains by affinity chromatography of biotinylated 3′UTR-COXIV RNA–protein complexes on streptavidin-conjugated paramagnetic particles. We successfully isolated two main proteins of about 86 and 42 kDa, whose sequences were highly attributable to Hsp90 and Actin. The purified proteins maintain RNA-binding ability and specificity for COXIV messenger and, interacting with the 3′UTR, then could negatively modulate mRNA tr…

Cytochemical and molecular analyses on mitochondria of immortalized and neoplastic epithelial cells from the human breast

STUDIO DELL’ESPRESSIONE DI GENI CODIFICANTI PROTEINE MITOCONDRIALI IN RATTUS NORVEGICUS.

Mitochondria and Development

Analysis of cytochrome oxidase subunits III and IV expression in debveloping rat brain.

Effetto del cadmio sull'attività mitocondriale e sull'espressione genica in cellule tumorali e immortalizzatedi epitelio ghiandolare mammario

Analysis of cytochrome C oxidase subunits III and IV expression in developing rat brain

Abstract Cytochrome c oxidase (COX) complex is built up with both nucleus- and mitochondrion-encoded subunits. Biogenesis and assembly of the complex thus requires fine cross-talk between the two compartments. In order to shed light on the regulation of nuclear–mitochondrial interactions, we studied the expression of COXIII (mitochondrion-encoded) and COXIV (nucleus-encoded) in adult rat tissues and rat developing brain. We found that the levels of COXIV protein and mRNA are not linearly related, thus suggesting a post-transcriptional mode of regulation. In agreement with this observation, we report the presence of a protein that specifically binds to the 3′-untranslated region of COXIV mRN…

Analysis of cytochrome c oxidase subunits III and IV in developing rat brain

Analysis of cytochrome oxidase subunits III and IV expression in developing rat brain.

Analysis of cytochrome c oxidase subunits III and IV expression in developing rat brain

Espressione del messaggero per l’Hsp56 in embrioni di Paracentrotus lividus

Mitochondrial protein expression in rattus norvegicus and human cells

Mitochondrial protein expression in rat and human cells.

Purification by affinity chromatography of H1 RNA-Binding Proteins from rat brain

Post-transcriptional regulation of mRNA metabolism is involved in processes as different as cell fate specification in development and cell response to a large variety of environmental cues. Regulation of all steps of RNA metabolism depends on RNA-binding proteins (RBPs). By using a T1 RNase protection assay, we previously identified three H1° RNA-binding factors (p40, p70 and p110), highly expressed in the rat brain. Here we report enrichment of these factors from brain extracts, obtained by affinity chromatography of biotinylated H1° RNA-protein complexes on streptavidin-conjugated paramagnetic particles. The purified proteins maintain RNA-binding ability and preference for histone messag…

Possible meccanisms regulating the expression of nuclear and mitochondrial genes

Effect of cadmium on mitochondria-related activity and gene expression in tumoral and immortalized human breast cells