title: Identification of oxygen-sensitive transcriptional programs in human embryonic stem cells.
abstract: To realize the full potential of human embryonic stem cells (hESCs), it is important to develop culture conditions that maintain hESCs in a pluripotent, undifferentiated state. A low O(2) atmosphere (approximately 4% O(2)), for example, prevents spontaneous differentiation and supports self-renewal of hESCs. To identify genes whose expression is sensitive to O(2) conditions, microarray analysis was performed on RNA from hESCs that had been maintained under either 4% or 20% O(2). Of 149 genes differentially expressed, 42 were up-regulated and 107 down-regulated under 20% O(2). Several of the down-regulated genes are most likely under the control of hypoxia-inducing factors and include genes encoding enzymes involved in carbohydrate catabolism and cellular redox state. Although genes associated with pluripotency, including OCT4, SOX2, and NANOG were generally unaffected, some genes controlled by these transcription factors, including LEFTY2, showed lowered expression under 20% O(2), while a few genes implicated in lineage specification were up-regulated. Although the differences between O(2) conditions were generally subtle, they were observed in two different hESC lines and at different passage numbers. The data are consistent with the hypothesis that 4% O(2) favors the molecular mechanisms required for the maintenance of pluripotency.
authors.affiliation: Department of Animal Sciences, University of Missouri, Columbia, Missouri 65211-7310, USA.
authors.forename: Suzanne D
authors.initials: SD
authors.lastname: Westfall
authors.forename: Shrikesh
authors.initials: S
authors.lastname: Sachdev
authors.forename: Padmalaya
authors.initials: P
authors.lastname: Das
authors.forename: Leonard B
authors.initials: LB
authors.lastname: Hearne
authors.forename: Mark
authors.initials: M
authors.lastname: Hannink
authors.forename: R Michael
authors.initials: RM
authors.lastname: Roberts
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Ezashi
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D015536:Down-Regulation / Q000187:drug effects; D053595:Embryonic Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D050437:Genes, Developmental; D006019:Glycolysis / Q000187:drug effects / Q000235:genetics; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics; D010100:Oxygen / Q000494:pharmacology*; D010427:Pentose Phosphate Pathway / Q000187:drug effects / Q000235:genetics; D039904:Pluripotent Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; D014157:Transcription Factors; D010100:Oxygen