30 research outputs found

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

    Get PDF

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

    Get PDF
    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

    Regulation of the human C-reactive protein gene, a major marker of inflammation and cancer

    No full text
    Human C-reactive protein (CRP) is the major acute phase reactant during inflammation. Regulation of CRP gene expression has been studied in two experimental systems: transgenic mice and human hepatoma cells. In the first system the human CRP gene flanked by approximately 10(4) bases of 5' and 3' sequences is expressed in a liver-specific and inducible manner. The chromatin configuration of the CRP transgene is characterized by the presence of constitutive and inducible liver-specific DNase I-hypersensitive sites. Inducible sites map precisely at the level of the CRP promoter region. In hepatoma cells we analysed the expression of the bacterial chloramphenicol acetyltransferase (CAT) gene driven by various segments of the CRP promoter. This latter approach has led to the identification of promoter elements responsive to interleukin-6 and of hepatocyte-specific nuclear proteins that interact with them

    Single-step purification and structural characterization of human interleukin-6 produced in Escherichia coli from a T7 RNA polymerase expression vector.

    No full text
    Human interleukin-6 or B-cell stimulatory factor-2 is a cytokine involved in acute phase and immune response. Cloning of cDNA for human interleukin-6 in the pT7.7 expression plasmid under the control of a bacteriophage T7 RNA polymerase promoter system allows rapid production of the cytokine in Escherichia coli. Upon cell induction with isopropyl thiogalactopyranoside, recombinant human interleukin-6 is overexpressed and forms insoluble inclusion bodies. Solubilization of the protein with 6 M guanidine hydrochloride and refolding in the presence of a reduction/oxidation system results in a quantitative recovery of recombinant human interleukin-6. This material is already 70% pure and can be further purified to homogeneity with a single passage over a weak anionic-exchange column. Extended structural characterization of the purified protein by electrospray mass spectrometry, automated Edman degradation and peptide mapping by high-pressure liquid chromatography/fast-atom-bombardment mass spectrometry demonstrates that recombinant human interleukin-6 is identical to the natural protein both in amino acid sequence and S-S bridge content. However, it contains a minor component accounting for about 20% of the entire translated protein which exhibits a Met-Ala dipeptide extension at the N-terminus. Purified recombinant human interleukin-6 is biologically active because it is able to induce at least 70-fold the human C-reactive promoter transfected in human hepatoma Hep 3B cells and is stable for several months in 10% glycerol at 4 degrees C. The expression system described in the present work has the main advantage of producing a high yield of recombinant human interleukin-6 (about 25 mg/l) combined with a very simple purification scheme.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

    I RAPPORTI CIVILISTICI NELL’INTERPRETAZIONE DELLA CORTE COSTITUZIONALERapporti civili - Rapporti etico-sociali

    No full text
    Il secondo tomo degli Atti del 2° Convegno Nazionale S.I.S.Di.C. ù dedicato ai contributi delle sessioni Rapporti civili e Rapporti Etico-sociali. Studiosi di aree diverse hanno rivisitato le complesse tematiche (Libertà costituzionali, Attuazione delle garanzie costituzionali, Famiglia e rapporti parentali, Diritto alla salute e qualità della vita) alla luce del contributo del Giudice delle Leggi, restituendo un quadro intelligibile delle ragioni storico-politiche che hanno influenzato l’attuale configurazione dell’ordinamento vigente

    Overexpressed nuclear factor-ÎșB can participate in endogenous C-reactive protein induction, and enhances the effects of C/EBPÎČ and signal transducer and activator of transcription-3

    No full text
    C-reactive protein (CRP), the prototypical human acute phase protein, is produced primarily by hepatocytes. Its expression is modestly induced by interleukin (IL)-6 in Hep3B cells while IL-1, which alone has no effect, synergistically enhances the effects of IL-6. In previous studies of the proximal CRP promoter, we found that signal transducer and activator of transcription-3 (STAT3) and C/EBPÎČ -mediated IL-6-induced transcription and that Rel p50 acted synergistically with C/EBPÎČ, in the absence of p65, to enhance CRP transcription. Neither a requirement nor a binding site for the classic nuclear factor (NF)-ÎșB heterodimer p50/p65 were found. The current studies were undertaken to determine whether similar novel transcription factor interactions might regulate the endogenous CRP gene. Transiently overexpressed p50 or p65 induced CRP mRNA accumulation in Hep3B cells. The heterodimer p50/p65 was markedly more effective than p50 or p65 homodimers. Co-overexpression of p50 or p65 with C/EBPÎČ or STAT3 synergistically enhanced CRP expression. Maximal expression was observed with overexpression of all four transcription factors; comparable effects were observed with IL-1ÎČ treatment of cells overexpressing STAT3 + C/EBPÎČ. Data from the Human Genome Project revealed 13 potential ÎșB sites in the first 4000 bases of the CRP promoter, only one of which, centred at −2652, bound nuclear p50/p65 heterodimer activated by IL-1ÎČ. Our findings indicate that classical NF-ÎșB activation can participate in endogenous CRP induction, and that activated NF-ÎșB may synergistically enhance the effects of C/EBPÎČ and STAT3. They raise the possibility, not as yet established, that NF-ÎșB activation may be responsible for the synergistic effect of IL-1ÎČ on IL-6-induced CRP expression
    corecore