Search results for "Protein Modification"
showing 8 items of 8 documents
Initiation and progression of atherosclerosis – enzymatic or oxidative modification of low-density lipoprotein?
2006
AbstractAtherosclerosis is widely regarded as a chronic inflammatory disease that develops as a consequence of entrapment of low-density lipoprotein (LDL) in the arterial intima. Native LDL lacks inflammatory properties, so the lipoprotein must undergo biochemical alterations to become atherogenic. Among several other candidates, two different concepts of lipoprotein modification are propagated, the widespread oxidation hypothesis and the less common E-LDL hypothesis, which proposes that modification of LDL occurs through the action of ubiquitous hydrolytic enzymes (enzymatically modified LDL or E-LDL) rather than oxidation. By clearly distinguishing between the initiation and progression o…
S-nitrosylation: An emerging post-translational protein modification in plants
2011
International audience; Increasing evidences support the assumption that nitric oxide (NO) acts as a physiological mediator in plants. Understanding its pleiotropic effects requires a deep analysis of the molecular mechanisms underlying its mode of action. In the recent years, efforts have been made in the identification of plant proteins modified by NO at the post-translational level, notably by S-nitrosylation. This reversible process involves the formation of a covalent bond between NO and reactive cysteine residues. This research has now born fruits and numerous proteins regulated by S-nitrosylation have been identified and characterized. This review describes the basic principle of S-n…
Sequence evolution, processing, and posttranslational modification of zonadhesin D domains in primates, as inferred from cDNA data
2005
Zonadhesin is a mammalian transmembrane sperm ligand. Precursor zonadhesin essentially consists of MAM (meprin/A5 antigen/mu receptor tyrosine phosphatase) domains, a mucin-like repeat, and D domains (homologous to von Willebrand D). Recent immunovisualization and binding assays indicate that zonadhesin D domains 1–3 bind postacrosomally to the zona pellucida. This feature has attracted considerable interest in the evolution of zonadhesin and its possible biological and biomedical implications. Previous molecular evolutionary analyses, however, were confined to cDNA sequences of only few distantly related species. Moreover, except for rabbit and pig, little is known about zonadhesin’s proce…
Investigation of Sudan IV staining areas in aortas of infants and children: Possible prelesional stages of atherogenesis
2009
Although atherosclerosis in infants and children is generally acknowledged, the temporal and spatial sequence of LDL insudation, modification and intimal monocyte accumulation has not been systematically studied. We have investigated herein very early stages of lesion formation in human aortas of individuals up to the age of 15 years. Aortic specimens from 61 cases (37 male, 24 female) were examined. 34 cases were1 year old, 16 cases were between 1 and 5 years old, and 11 cases were between 6 and 15 years old. Areas preselected under a dissection microscope after Sudan IV staining were investigated in depth by immunohistochemical staining for apolipoprotein B, monocytes/macrophages, smooth …
Protein S-nitrosylation: What's going on in plants?
2012
International audience; Nitric oxide (NO) is now recognized as a key regulator of plant physiological processes. Understanding the mechanisms by which NO exerts its biological functions has been the subject of extensive research. Several components of the signaling pathways relaying NO effects in plants, including second messengers, protein kinases, phytohormones, and target genes, have been characterized. In addition, there is now compelling experimental evidence that NO partly operates through posttranslational modification of proteins, notably via S-nitrosylation and tyrosine nitration. Recently, proteome-wide scale analyses led to the identification of numerous protein candidates for S-…
Enzymatic modification of low-density lipoprotein in the arterial wall: a new role for plasmin and matrix metalloproteinases in atherogenesis.
2004
Objective— Functionally interactive proteases of the plasminogen/plasmin and the matrix metalloproteinase (MMP) system degrade and reorganize the extracellular matrix of the vessel wall in atherosclerosis. Here we investigated whether such proteases are able to confer atherogenic properties onto low density lipoprotein by nonoxidative modification. Methods and Results— Similar to the recently described enzymatically-modified low-density lipoprotein (E-LDL), native LDL exposed to plasmin or matrix MMP-2 or MMP-9 and cholesterylester-hydrolase (CEH) showed extensive deesterification, with ratios of free cholesterol to total cholesterol rising to 0.8 compared with 0.2 in native LDL. When the …
Redox signaling (cross-talk) from and to mitochondria involves mitochondrial pores and reactive oxygen species
2010
This review highlights the important role of redox signaling between mitochondria and NADPH oxidases. Besides the definition and general importance of redox signaling, the cross-talk between mitochondrial and Nox-derived reactive oxygen species (ROS) is discussed on the basis of 4 different examples. In the first model, angiotensin-II is discussed as a trigger for NADPH oxidase activation with subsequent ROS-dependent opening of mitochondrial ATP-sensitive potassium channels leading to depolarization of mitochondrial membrane potential followed by mitochondrial ROS formation and respiratory dysfunction. This concept was supported by observations that ethidium bromide-induced mitochondrial d…
New frontiers in nitric oxide biology in plant.
2011
Preface; International audience