MicroRNA expression patterns and function in endodermal differentiation of human embryonic stem cells.
OBJECTIVE
microRNAs (miRNAs) are small noncoding RNAs that regulate cognate mRNAs post-transcriptionally. Human embryonic stem cells (hESC), which exhibit the characteristics of pluripotency and self-renewal, may serve as a model to study the role of miRNAs in early human development. We aimed to determine whether endodermally-differentiated hESC demonstrate a unique miRNA expression pattern, and whether overexpression of endoderm-specific miRNA may affect hESC differentiation.


METHODS
miRNA expression was profiled in undifferentiated and NaButyrate-induced differentiated hESC of two lines, using microarray and quantitative RT-PCR. Then, the effect of lentiviral-based overexpression of liver-specific miR-122 on hESC differentiation was analyzed, using genomewide gene microarrays.


RESULTS
The miRNA profiling revealed expression of three novel miRNAs in undifferentiated and differentiated hESC. Upon NaButyrate induction, two of the most upregulated miRNAs common to both cell lines were miR-24 and miR-10a, whose target genes have been shown to inhibit endodermal differentiation. Furthermore, induction of several liver-enriched miRNAs, including miR-122 and miR-192, was observed in parallel to induction of endodermal gene expression. Stable overexpression of miR-122 in hESC was unable to direct spontaneous differentiation towards a clear endodermal fate, but rather, delayed general differentiation of these cells.


CONCLUSIONS
Our results demonstrate that expression of specific miRNAs correlates with that of specific genes upon differentiation, and highlight the potential role of miRNAs in endodermal differentiation of hESC.
Tzur
Galit
G
Goldyne Savad Institute of Gene Therapy, Hadassah University Hospital, Jerusalem, Israel.
Levy
Asaf
A
Meiri
Eti
E
Barad
Omer
O
Spector
Yael
Y
Bentwich
Zvi
Z
Mizrahi
Lina
L
Katzenellenbogen
Mark
M
Ben-Shushan
Etti
E
Reubinoff
Benjamin E
BE
Galun
Eithan
E
D000465:Algorithms; D002454:Cell Differentiation; D002460:Cell Line; D053595:Embryonic Stem Cells / Q000166:cytology*; D004707:Endoderm / Q000378:metabolism*; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D005822:Genetic Vectors; D015894:Genome, Human; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012978:Sodium Oxybate / Q000494:pharmacology; D014157:Transcription Factors / Q000378:metabolism
D035683:MicroRNAs; D014157:Transcription Factors; D012978:Sodium Oxybate