Eukaryotic DING Proteins Are Endogenous: An Immunohistological Study in Mouse Tissues

• Published in: PloS one Vol. 5; no. 2; p. e9099
• Main Authors: Collombet, Jean-Marc, Elias, Mikael, Gotthard, Guillaume, Four, Elise, Renault, Frédérique, Joffre, Aurélie, Baubichon, Dominique, Rochu, Daniel, Chabrière, Eric
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 08.02.2010; Public Library of Science (PLoS)
• Subjects: Animal tissues; Animals; Antibodies, Monoclonal - immunology; Antibody Specificity - immunology; Antigens; Apolipoproteins; Arteriosclerosis; Arthritis; Atherosclerosis; Biochemistry; Blotting, Western; Brain Chemistry; Cell Biology; Cell cycle; Cerebral Cortex - chemistry; Cerebral Cortex - cytology; Contaminants; Coronary vessels; Deoxyribonucleic acid; DNA; Eukaryotes; Eukaryotic Cells - metabolism; Genetics and Genomics; Germfree; Hippocampus - chemistry; Hippocampus - cytology; HIV; Human immunodeficiency virus; Immunohistochemistry; Immunology; Isoforms; Laboratories; Liver - chemistry; Localization; Lung - chemistry; Male; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Molecular Weight; Neurons; Neurons - chemistry; Pathology; Phosphatase; Physiology; Poisoning; Polycomb Repressive Complex 1; Protein Isoforms - chemistry; Protein Isoforms - metabolism; Proteins; Repressor Proteins - blood; Repressor Proteins - immunology; Repressor Proteins - metabolism; Rheumatoid arthritis; Rheumatoid factor; Skin - chemistry; Tissues; Ubiquitin-Protein Ligases; Veins & arteries; Zinc Fingers; France
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0009099

DING proteins encompass an intriguing protein family first characterized by their conserved N-terminal sequences. Some of these proteins seem to have key roles in various human diseases, e.g., rheumatoid arthritis, atherosclerosis, HIV suppression. Although this protein family seems to be ubiquitous in eukaryotes, their genes are consistently lacking from genomic databases. Such a lack has considerably hampered functional studies and has fostered therefore the hypothesis that DING proteins isolated from eukaryotes were in fact prokaryotic contaminants. In the framework of our study, we have performed a comprehensive immunological detection of DING proteins in mice. We demonstrate that DING proteins are present in all tissues tested as isoforms of various molecular weights (MWs). Their intracellular localization is tissue-dependant, being exclusively nuclear in neurons, but cytoplasmic and nuclear in other tissues. We also provide evidence that germ-free mouse plasma contains as much DING protein as wild-type. Hence, data herein provide a valuable basis for future investigations aimed at eukaryotic DING proteins, revealing that these proteins seem ubiquitous in mouse tissue. Our results strongly suggest that mouse DING proteins are endogenous. Moreover, the determination in this study of the precise cellular localization of DING proteins constitute a precious evidence to understand their molecular involvements in their related human diseases.