Int J Stem Cells.  2014 Nov;7(2):108-117. 10.15283/ijsc.2014.7.2.108.

Transcriptional Profiles of Imprinted Genes in Human Embryonic Stem Cells During In vitro Differentiation

• Park SW
• Do HS
• Kim D
• Ko JY
• Lee SH
• Han YM

• KMID: 1974598
• DOI: http://doi.org/10.15283/ijsc.2014.7.2.108

Abstract

BACKGROUND AND OBJECTIVES
Genomic imprinting is an inheritance phenomenon by which a subset of genes are expressed from one allele of two homologous chromosomes in a parent of origin-specific manner. Even though fine-tuned regulation of genomic imprinting process is essential for normal development, no other means are available to study genomic imprinting in human during embryonic development. In relation with this bottleneck, differentiation of human embryonic stem cells (hESCs) into specialized lineages may be considered as an alternative to mimic human development.
METHODS AND RESULTS
In this study, hESCs were differentiated into three lineage cell types to analyze temporal and spatial expression of imprinted genes. Of 19 imprinted genes examined, 15 imprinted genes showed similar transcriptional level among two hESC lines and two human induced pluripotent stem cell (hiPSC) lines. Expressional patterns of most imprinted genes were varied in progenitors and fully differentiated cells which were derived from hESCs. Also, no consistence was observed in the expression pattern of imprinted genes within an imprinting domain during in vitro differentiation of hESCs into three lineage cell types.
CONCLUSIONS
Transcriptional expression of imprinted genes is regulated in a cell type-specific manner in hESCs during in vitro differentiation.

Keyword

Human embryonic stem cells; Genomic imprinting; In vitro differentiation; Transcriptional expression

MeSH Terms

Alleles
Embryonic Development
Embryonic Stem Cells*
Female
Genomic Imprinting
Human Development
Humans
Parents
Pluripotent Stem Cells
Pregnancy
Wills

Figure

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  Fig. 1. Transcriptional expression of imprinted genes between four hPSC lines. Transcriptional levels of the imprinted genes that are included in IGF2-H19 (A), DIO3-DLK1 (B), KCNQ1 (C), PWS/AS (D), and PEG10 (E) domains were examined in undifferentiated hPSCs by qRT-PCR. The error bars indicate±SD for three independent experiments (n=3, *p<0.05, **p <0.01). Abbreviations: CRL_iPSCs; hiPSCs derived from CRL foreskin fibroblasts, HDF_iPSCs; hiPSCs derived from human dermal fibro-blasts.

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  Fig. 2. Relative expression levels of imprinted genes in IGF2/H19 domain in hESCs during in vitro differentiation. (A) A schematic diagram of IGF2/H19 domain (Ch 11p15). Relative expression level of IGF and H19 imprinted genes in hESCs during in vitro differentiation to DA neurons (B), osteoblasts (C), and hepatocytes (D). The error bars indicate±SD for three independent experiments (n=3, *p<0.05, **p<0.01, ***p<0.001). Abbreviations, ES: H9-hESCs; NP: neuronal progenitors; DA: dopaminergic neurons; MP: mesenchymal progenitors; OB: osteoblasts; DE: definitive endoderm; HEP: hepatocytes.

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  Fig. 3. Relative expression levels of imprinted genes in KCNQ1 domain in hESCs during in vitro differentiation. (A) A schematic diagram of KCNQ1 domain (Ch 11p15). This KCNQ1 domain contains several imprinted genes, including OSBPL5, PHLDA2, CDKN1C, KCNQ1, and KCNQ1OT1. Relative expression level of several imprinted genes in hESCs during in vitro differentiation to DA neurons (B), osteoblasts (C), and hepatocytes (D). The error bars indicate±SD for three independent experiments (n=3, *p<0.05, **p<0.01, ***p<0.001).

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  Fig. 4. Relative expression levels of imprinted genes in PWS/AS domain in hESCs during in vitro differentiation. (A) A schematic diagram of PWS/AS domain (Ch. 15q11-q13). This domain contains several imprinted genes, including MAGEL2, NDN, SNRPN, IPW, UBE3A, and ATP10A. Relative expression level of several imprinted genes in hESCs during in vitro differentiation to DA neurons (B), osteoblasts (C), and hepatocytes (D). The error bars indicate±SD for three independent experiments (n=3, *p<0.05, **p<0.01, ***p<0.001).

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  Fig. 5. Relative expression levels of imprinted genes in PEG10 domain in hESCs during in vitro differentiation. (A) A schematic diagram of PEG10 domain (Ch. 7q21.3). This domain contains three imprinted genes such as SGCE, PEG10 and PPP1R9A. Relative expression level of these imprinted genes in hESCs during in vitro differentiation to DA neurons (B), osteoblasts (C), and hepatocytes (D). The error bars indicate±SD for three independent experiments (n=3, *p<0.05, **p<0.01, ***p<0.001).

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  Fig. 6. Relative expression levels of imprinted genes in DIO3-DLK1 domain in hESCs during in vitro differentiation. (A) A schematic diagram of DIO3-DLK1 domain (Ch. 14q32.2). This domain contains four imprinted genes such as DLK1, MEG3, DIO3 and RTL1. Relative expression level of DIO3 and RTL1 imprinted genes in hESCs during in vitro differentiation to DA neurons (B), osteoblasts (C), and hepatocytes (D). The error bars indicate±SD for three independent experiments (n=3, *p<0.05, **p<0.01, ***p<0.001).

Reference

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