title: Characterization of the differential expression of uncoupling protein 2 and ROS production in differentiated mouse macrophage-cells (Mm1) and the progenitor cells (M1).
abstract: The expression status of mitochondrial uncoupling protein 2 (UCP2) was investigated in undifferentiated mouse myeloid leukemia (M1) and its differentiated macrophage-like cells (Mm1). Mm1 cells have a high ability of phagocytosis along with significantly high levels of reactive oxygen species (ROS) production, UCP2 protein and manganese superoxide dismutase (Mn-SOD), in contrast to undifferentiated leukemia cells (M1). Mm1 cells expressed 10-fold more UCP2 protein compared with undifferentiated M1 cells, although the UCP2 mRNA levels in both cell types were similar. The higher expression of UCP2 in the Mm1 cells suggests a regulatory role of UCP2 in the ROS production. Furthermore, the transfection of UCP2-GFP-expression vector in Mm1 cells dissipated the mitochondrial membrane potential and reduced ROS production, which was shown by their direct visualization using MitoTracker Red CM-H2Xros. The macrophage gp91phox protein, a membrane catalytic component of the NADPH oxidase complex, was at a similar level in both of UCP2-GFP expressed and non-expressed Mm1 cells. These results suggest that the UCP2 protein of the undifferentiated cell is regulated at a quite low level and the higher UCP2 protein of the differentiated macrophages involves with the regulation of ROS production.
authors.affiliation: Department of Anatomy and Cell Biology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, 466-8550, Showa-ku, Nagoya, Aichi, Japan. knishio@med.nagoya-u.ac.jp
authors.forename: Koji
authors.initials: K
authors.lastname: Nishio
authors.forename: Shanlou
authors.initials: S
authors.lastname: Qiao
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Yamashita
mesh_terms: D000818:Animals; D002460:Cell Line; D005786:Gene Expression Regulation; D007473:Ion Channels; D007951:Leukemia, Myeloid / Q000378:metabolism; D008264:Macrophages / Q000201:enzymology / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000032:analysis / Q000378:metabolism; D008564:Membrane Potentials; D026901:Membrane Transport Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008928:Mitochondria / Q000737:chemistry / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000032:analysis / Q000378:metabolism; D010587:Phagocytosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013234:Stem Cells / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000032:analysis / Q000378:metabolism; D015533:Transcriptional Activation; D000071246:Uncoupling Protein 2
chemical_list: D007473:Ion Channels; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C000604390:Ucp2 protein, mouse; C000604391:Ucp2 protein, rat; D000071246:Uncoupling Protein 2; D013482:Superoxide Dismutase; C488842:Cybb protein, mouse; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases