Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes.
BACKGROUND
Characterization of gene expression signatures for cardiomyocytes derived from embryonic stem cells will help to define their early biologic processes.


RESULTS
A transgenic alpha-myosin heavy chain (MHC) embryonic stem cell lineage was generated, exhibiting puromycin resistance and expressing enhanced green fluorescent protein (EGFP) under the control of the alpha-MHC promoter. A puromycin-resistant, EGFP-positive, alpha-MHC-positive cardiomyocyte population was isolated with over 92% purity. RNA was isolated after electrophysiological characterization of the cardiomyocytes. Comprehensive transcriptome analysis of alpha-MHC-positive cardiomyocytes in comparison with undifferentiated alpha-MHC embryonic stem cells and the control population from 15-day-old embryoid bodies led to identification of 884 upregulated probe sets and 951 downregulated probe sets in alpha-MHC-positive cardiomyocytes. A subset of upregulated genes encodes cytoskeletal and voltage-dependent channel proteins, and proteins that participate in aerobic energy metabolism. Interestingly, mitosis, apoptosis, and Wnt signaling-associated genes were downregulated in the cardiomyocytes. In contrast, annotations for genes upregulated in the alpha-MHC-positive cardiomyocytes are enriched for the following Gene Ontology (GO) categories: enzyme-linked receptor protein signaling pathway (GO:0007167), protein kinase activity (GO:0004672), negative regulation of Wnt receptor signaling pathway (GO:0030178), and regulation of cell size (O:0008361). They were also enriched for the Biocarta p38 mitogen-activated protein kinase signaling pathway and Kyoto Encyclopedia of Genes and Genomes (KEGG) calcium signaling pathway.


CONCLUSIONS
The specific pattern of gene expression in the cardiomyocytes derived from embryonic stem cells reflects the biologic, physiologic, and functional processes that take place in mature cardiomyocytes. Identification of cardiomyocyte-specific gene expression patterns and signaling pathways will contribute toward elucidating their roles in intact cardiac function.
Doss
Michael Xavier
MX
Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne, Cologne, Germany. m-x.doss@uni-koeln.de
Winkler
Johannes
J
Chen
Shuhua
S
Hippler-Altenburg
Rita
R
Sotiriadou
Isaia
I
Halbach
Marcel
M
Pfannkuche
Kurt
K
Liang
Huamin
H
Schulz
Herbert
H
Hummel
Oliver
O
Hübner
Norbert
N
Rottscheidt
Ruth
R
Hescheler
Jürgen
J
Sachinidis
Agapios
A
D000818:Animals; D017209:Apoptosis / Q000235:genetics; D002454:Cell Differentiation; D049109:Cell Proliferation; D016000:Cluster Analysis; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D005818:Genetic Engineering; D051379:Mice; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism*; D024723:Ventricular Myosins / Q000235:genetics
D012333:RNA, Messenger; D024723:Ventricular Myosins