title: Gene expression signatures of seven individual human embryonic stem cell lines.
abstract: Identification of molecular components that define a pluripotent human embryonic stem cell (hESC) provides the basis for understanding the molecular mechanisms regulating the maintenance of pluripotency and induction of differentiation. We compared the gene expression profiles of seven genetically independent hESC lines with those of nonlineage-differentiated cells derived from each line. A total of 8,464 transcripts were expressed in all hESC lines. More than 45% of them have no yet-known biological function, which indicates that a high number of unknown factors contribute to hESC pluripotency. Among these 8,464 transcripts, 280 genes were specific for hESCs and 219 genes were more than twofold differentially expressed in all hESC lines compared with nonlineage-differentiated cells. They represent genes implicated in the maintenance of pluripotency and those involved in early differentiation. The chromosomal distribution of these hESC-enriched genes showed over-representation in chromosome 19 and under-representation in chromosome 18. Although the overall gene expression profiles of the seven hESC lines were markedly similar, each line also had a subset of differentially expressed genes reflecting their genetic variation and possibly preferential differentiation potential. Limited overlap between gene expression profiles illustrates the importance of cross-validation of results between different ESC lines.
authors.affiliation: Turku Centre for Biotechnology, University of Turku and Abo Akademi University, POB 123, 0520 Turku, Finland. Heli.Skottman@btk.fi
authors.forename: Heli
authors.initials: H
authors.lastname: Skottman
authors.forename: Milla
authors.initials: M
authors.lastname: Mikkola
authors.forename: Karolina
authors.initials: K
authors.lastname: Lundin
authors.forename: Cia
authors.initials: C
authors.lastname: Olsson
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Strömberg
authors.forename: Timo
authors.initials: T
authors.lastname: Tuuri
authors.forename: Timo
authors.initials: T
authors.lastname: Otonkoski
authors.forename: Outi
authors.initials: O
authors.lastname: Hovatta
authors.forename: Riitta
authors.initials: R
authors.lastname: Lahesmaa
mesh_terms: D002454:Cell Differentiation / Q000235:genetics; D002460:Cell Line; D004622:Embryo, Mammalian / Q000166:cytology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D046228:Microarray Analysis; D017711:Nonlinear Dynamics; D039904:Pluripotent Stem Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics