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A. Dutriaux

Bio: A. Dutriaux is an academic researcher from Johns Hopkins University School of Medicine. The author has contributed to research in topics: DNA damage & Vault (architecture). The author has an hindex of 1, co-authored 1 publications receiving 2775 citations.

Papers
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Journal ArticleDOI
20 Nov 1998-Science
TL;DR: After DNA damage, many cells appear to enter a sustained arrest in the G2 phase of the cell cycle but this arrest could be sustained only when p53 was present in the cell and capable of transcriptionally activating the cyclin-dependent kinase inhibitor p21.
Abstract: After DNA damage, many cells appear to enter a sustained arrest in the G 2 phase of the cell cycle. It is shown here that this arrest could be sustained only when p53 was present in the cell and capable of transcriptionally activating the cyclin-dependent kinase inhibitor p21. After disruption of either the p53 or the p21 gene, γ radiated cells progressed into mitosis and exhibited a G 2 DNA content only because of a failure of cytokinesis. Thus, p53 and p21 appear to be essential for maintaining the G 2 checkpoint in human cells.

2,882 citations

Journal ArticleDOI
TL;DR: In this article , a simplified procedure that combines human vault expression in the yeast Komagataella phaffii, as described in a recent report, and a purification process was developed.
Abstract: The vault nanoparticle is a eukaryotic assembly consisting of 78 copies of the 99-kDa major vault protein. They generate two cup-shaped symmetrical halves, which in vivo enclose protein and RNA molecules. Overall, this assembly is mainly involved in pro-survival and cytoprotective functions. It also holds a remarkable biotechnological potential for drug/gene delivery, thanks to its huge internal cavity and the absence of toxicity/immunogenicity. The available purification protocols are complex, partly because they use higher eukaryotes as expression systems. Here, we report a simplified procedure that combines human vault expression in the yeast Komagataella phaffii, as described in a recent report, and a purification process we have developed. This consists of RNase pretreatment followed by size-exclusion chromatography, which is far simpler than any other reported to date. Protein identity and purity was confirmed by SDS-PAGE, Western blot and transmission electron microscopy. We also found that the protein displayed a significant propensity to aggregate. We thus investigated this phenomenon and the related structural changes by Fourier-transform spectroscopy and dynamic light scattering, which led us to determine the most suitable storage conditions. In particular, the addition of either trehalose or Tween-20 ensured the best preservation of the protein in native, soluble form.

Cited by
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Journal ArticleDOI
06 Feb 2004-Science
TL;DR: In this article, the authors identify potent and selective small-molecule antagonists of MDM2 and confirm their mode of action through the crystal structures of complexes, leading to cell cycle arrest, apoptosis, and growth inhibition of human tumor xenografts.
Abstract: MDM2 binds the p53 tumor suppressor protein with high affinity and negatively modulates its transcriptional activity and stability. Overexpression of MDM2, found in many human tumors, effectively impairs p53 function. Inhibition of MDM2-p53 interaction can stabilize p53 and may offer a novel strategy for cancer therapy. Here, we identify potent and selective small-molecule antagonists of MDM2 and confirm their mode of action through the crystal structures of complexes. These compounds bind MDM2 in the p53-binding pocket and activate the p53 pathway in cancer cells, leading to cell cycle arrest, apoptosis, and growth inhibition of human tumor xenografts in nude mice.

4,397 citations

Journal ArticleDOI
23 Nov 2000-Nature
TL;DR: The inability to repair DNA damage properly in mammals leads to various disorders and enhanced rates of tumour development, and this work has shown that direct activation of DNA repair networks is needed to correct this problem.
Abstract: The inability to repair DNA damage properly in mammals leads to various disorders and enhanced rates of tumour development. Organisms respond to chromosomal insults by activating a complex damage response pathway. This pathway regulates known responses such as cell-cycle arrest and apoptosis (programmed cell death), and has recently been shown to control additional processes including direct activation of DNA repair networks.

3,230 citations

Journal ArticleDOI
TL;DR: This Review focuses on recent advances in the understanding of the regulation of p21 and its biological functions with emphasis on its p53-independent tumour suppressor activities and paradoxical tumour-promoting activities, and their implications in cancer.
Abstract: One of the main engines that drives cellular transformation is the loss of proper control of the mammalian cell cycle. The cyclin-dependent kinase inhibitor p21 (also known as p21WAF1/Cip1) promotes cell cycle arrest in response to many stimuli. It is well positioned to function as both a sensor and an effector of multiple anti-proliferative signals. This Review focuses on recent advances in our understanding of the regulation of p21 and its biological functions with emphasis on its p53-independent tumour suppressor activities and paradoxical tumour-promoting activities, and their implications in cancer.

2,247 citations

Journal ArticleDOI
TL;DR: It is demonstrated that microRNAs (miRNAs) are important components of the p53 transcriptional network and miR-34a-responsive genes are highly enriched for those that regulate cell-cycle progression, apoptosis, DNA repair, and angiogenesis.

2,008 citations

Journal ArticleDOI
TL;DR: The various features of cellular senescence are reviewed and their contribution to tumor suppression is discussed and the power and limitations of the biomarkers currently used to identify senescent cells in vitro and in vivo are highlighted.
Abstract: Almost half a century after the first reports describing the limited replicative potential of primary cells in culture, there is now overwhelming evidence for the existence of “cellular senescence” in vivo. It is being recognized as a critical feature of mammalian cells to suppress tumorigenesis, acting alongside cell death programs. Here, we review the various features of cellular senescence and discuss their contribution to tumor suppression. Additionally, we highlight the power and limitations of the biomarkers currently used to identify senescent cells in vitro and in vivo.

1,838 citations