title: Mitochondrial and metabolic remodeling during reprogramming and differentiation of the reprogrammed cells.
abstract: Reprogramming is one of the most essential areas of research in stem cell biology. Despite this importance, the mechanism and correlates of reprogramming remain largely unknown. In this study, we investigated the cytoplasmic remodeling and changes in metabolism that occur during reprogramming and differentiation of pluripotent stem cells. Specifically, we examined the cellular organelles of three pluripotent stem cells, embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and epiblast stem cells (EpiSCs), by electron microscopy. We found that the cellular organelles of primed pluripotent EpiSCs were more similar to those of naive pluripotent ESCs and iPSCs than somatic cells. EpiSCs, as well as ESCs and iPSCs, contain large nuclei, poorly developed endoplasmic reticula, and underdeveloped cristae; however, their mitochondria were still mature relative to the mitochondria of ESCs and iPSCs. Next, we differentiated these pluripotent stem cells into neural stem cells (NSCs) in vitro and compared the morphology of organelles. We found that the morphology of organelles of NSCs differentiated from ESCs, iPSCs, and EpiSCs was indistinguishable from brain-derived NSCs. Finally, we examined the changes in energy metabolism that accompanied mitochondrial remodeling during reprogramming and differentiation. We found that the glycolytic activity of ESCs and iPSCs was greater compared with EpiSCs, and that the glycolytic activity of EpiSCs was greater compared with NSCs differentiated from ESCs, iPSCs, and EpiSCs. These results suggest that a change in the cellular state is accompanied by dynamic changes in the morphology of cytoplasmic organelles and corresponding changes in energy metabolism.
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Choi
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Jin Hoi
authors.initials: JH
authors.lastname: Kim
authors.affiliation: 2Fertility Research Institute, Seoul Rachel Fertility Center, Seoul, Republic of Korea.
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Chung
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Yean Ju
authors.initials: YJ
authors.lastname: Hong
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Hyun Sik
authors.initials: HS
authors.lastname: Jang
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Bong Jong
authors.initials: BJ
authors.lastname: Seo
authors.affiliation: 3Department of Stem Cell Biology, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Taek Hee
authors.initials: TH
authors.lastname: Jung
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Jong Soo
authors.initials: JS
authors.lastname: Kim
authors.affiliation: 3Department of Stem Cell Biology, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Hyung Min
authors.initials: HM
authors.lastname: Chung
authors.affiliation: 4Animal Biotechnology Division, National Institute of Animal Science, Rural Development Administration, Suwon, Republic of Korea.
authors.forename: Sung June
authors.initials: SJ
authors.lastname: Byun
authors.affiliation: 5Department of Food Science and Biotechnology of Animal Resources, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Sung Gu
authors.initials: SG
authors.lastname: Han
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Han Geuk
authors.initials: HG
authors.lastname: Seo
authors.affiliation: 1Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea.
authors.forename: Jeong Tae
authors.initials: JT
authors.lastname: Do
mesh_terms: D000818:Animals; D002460:Cell Line; D065150:Cellular Reprogramming; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D006019:Glycolysis; D057026:Induced Pluripotent Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D051379:Mice; D008928:Mitochondria / Q000378:metabolism* / Q000648:ultrastructure; D058953:Neural Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure