Homogenous protein programming in the mammalian left and right ventricle free walls
Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, Bethesda, MD 20892-1061, USA.Physiological Genomics (Impact Factor: 2.37). 08/2011; 43(21):1198-206. DOI: 10.1152/physiolgenomics.00121.2011
Despite identical cardiac outputs, the right (RV) and left ventricle (LV) have very different embryological origins and resting workload. These differences suggest that the ventricles have different protein programming with regard to energy metabolism and contractile elements. The objective of this study was to determine the relative RV and LV protein expression levels, with an emphasis on energy metabolism. The RV and LV protein contents of the rabbit and porcine heart were determined with quantitative gel electrophoresis (2D-DIGE), mass spectrometry, and optical spectroscopy techniques. Surprisingly, the expression levels for more than 600 RV and LV proteins detected were similar. This included proteins many different compartments and metabolic pathways. In addition, no isoelectric shifts were detected in 2D-DIGE consistent with no differential posttranslational modifications in these proteins. Analysis of the RV and LV metabolic response to work revealed that the metabolic rate increases much faster with workload in the RV compared with LV. This implies that the generally lower metabolic stress of the RV actually approaches LV metabolic stress at maximum workloads. Thus, identical levels of energy conversion and mechanical elements in the RV and LV may be driven by the performance requirements at maximum workloads. In summary, the ventricles of the heart manage the differences in overall workload by modifying the amounts of cytosol, not its composition. The constant myocyte composition in the LV and RV implies that the ratio of energy metabolism and contractile elements may be optimal for the sustained cardiac contractile activity in the mammalian heart.
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- "The myocardium has been a target of proteomic endeavours . In this sense, quantitative gel electrophoresis and MS were used to compare right and left ventricle protein expression , and this led to identification of 600 proteins with no differential PTMs shared between the ventricles . The proteome of cardiac cells in different cardiomyopathies has also been addressed. "
ABSTRACT: Traditional biomedical models are easy to manage in experimental facilities and allow fast and affordable basic genetic studies related to human disorders, but in some cases they do not always represent the complexity of their physiology. Translational medicine demands selected models depending on the particularities of the human disease to be investigated, reproducing as closely as possible the evolution, clinical symptoms and molecular pathways, cells or tissues involved in the dysfunction. Thus, pig models offer an alternative because of their anatomical and physiological similarities to humans and the availability of genomic, transcriptomic and, progressively more, proteomic tools for analysis of this species. Furthermore, there is a wide range of natural, selected and transgenic porcine breeds. The present review provides a summary of the applications of the pig as a model for metabolic, cardiovascular, infectious diseases, xenotransplantation and neurological disorders and an overview of the possibilities that the diverse proteomic techniques offer to study these pathologies in depth.This article is protected by copyright. All rights reservedPROTEOMICS - CLINICAL APPLICATIONS 10/2014; 8(9-10). DOI:10.1002/prca.201300099 · 2.96 Impact Factor
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ABSTRACT: The concentration of mitochondrial oxidative phosphorylation complexes (MOPCs) is tuned to the maximum energy conversion requirements of a given tissue; however, whether the activity of MOPCs is altered in response to acute changes in energy conversion demand is unclear. We hypothesized that MOPCs activity is modulated by tissue metabolic stress to maintain the energy-metabolism homeostasis. Metabolic stress was defined as the observed energy conversion rate/maximum energy conversion rate. The maximum energy conversion rate was assumed to be proportional to the concentration of MOPCs, as determined with optical spectroscopy, gel electrophoresis, and mass spectrometry. The resting metabolic stress of the heart and liver across the range of resting metabolic rates within an allometric series (mouse, rabbit, and pig) was determined from MPOCs content and literature respiratory values. The metabolic stress of the liver was high and nearly constant across the allometric series due to the proportional increase in MOPCs content with resting metabolic rate. In contrast, the MOPCs content of the heart was essentially constant in the allometric series, resulting in an increasing metabolic stress with decreasing animal size. The MOPCs activity was determined in native gels, with an emphasis on Complex V. Extracted MOPCs enzyme activity was proportional to resting metabolic stress across tissues and species. Complex V activity was also shown to be acutely modulated by changes in metabolic stress in the heart, in vivo and in vitro. The modulation of extracted MOPCs activity suggests that persistent posttranslational modifications (PTMs) alter MOPCs activity both chronically and acutely, specifically in the heart. Protein phosphorylation of Complex V was correlated with activity inhibition under several conditions, suggesting that protein phosphorylation may contribute to activity modulation with energy metabolic stress. These data are consistent with the notion that metabolic stress modulates MOPCs activity in the heart.AJP Regulatory Integrative and Comparative Physiology 02/2012; 302(9):R1034-48. DOI:10.1152/ajpregu.00596.2011 · 3.11 Impact Factor
- The Journal of General Physiology 06/2012; 139(6):407-14. DOI:10.1085/jgp.201210783 · 4.79 Impact Factor
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