MicroRNA Expression Profiling of Oligodendrocyte Differentiation from Human Embryonic Stem Cells

Abstract

BackgroundCells of the oligodendrocyte (OL) lineage play a vital role in the production and maintenance of myelin, a multilamellar membrane which allows for saltatory conduction along axons. These cells may provide immense therapeutic potential for lost sensory and motor function in demyelinating conditions, such as spinal cord injury, multiple sclerosis, and transverse myelitis. However, the molecular mechanisms controlling OL differentiation are largely unknown. MicroRNAs (miRNAs) are considered the “micromanagers” of gene expression with suggestive roles in cellular differentiation and maintenance. Although unique patterns of miRNA expression in various cell lineages have been characterized, this is the first report documenting their expression during oligodendrocyte maturation from human embryonic stem (hES) cells. Here, we performed a global miRNA analysis to reveal and identify characteristic patterns in the multiple stages leading to OL maturation from hES cells including those targeting factors involved in myelin production.Methodology/Principal FindingsWe isolated cells from 8 stages of OL differentiation. Total RNA was subjected to miRNA profiling and validations preformed using real-time qRT-PCR. A comparison of miRNAs from our cultured OLs and OL progenitors showed significant similarities with published results from equivalent cells found in the rat and mouse central nervous system. Principal component analysis revealed four main clusters of miRNA expression corresponding to early, mid, and late progenitors, and mature OLs. These results were supported by correlation analyses between adjacent stages. Interestingly, the highest differentially-expressed miRNAs demonstrated a similar pattern of expression throughout all stages of differentiation, suggesting that they potentially regulate a common target or set of targets in this process. The predicted targets of these miRNAs include those with known or suspected roles in oligodendrocyte development and myelination including C11Orf9, CLDN11, MYTL1, MBOP, MPZL2, and DDR1.Conclusions/SignificanceWe demonstrate miRNA profiles during distinct stages in oligodendroglial differentiation that may provide key markers of OL maturation. Our results reveal pronounced trends in miRNA expression and their potential mRNA target interactions that could provide valuable insight into the molecular mechanisms of differentiation.

Contribution of MicroRNA-1275 to Claudin11 Protein Suppression via a Polycomb-mediated Silencing Mechanism in Human Glioma Stem-like Cells

“…Although miR-205 has been reported as a potential regulator of CLDN11 in human embryonic stem cell differentiation, this miRNA did not appear to be involved in GSC differentiation into oligodendroglial lineage in our model (35). Another miRNA, miR-219, has been shown to be necessary and sufficient to promote oligodendrocyte differentiation (44).…”

“…1, A and B). We also analyzed the expression levels of miR-205 in GSCs, which has been reported as a potential regulator of CLDN11 in human embryonic stem cell differentiation (35), and found that miR-205 expression was at an extremely low level, and there was no evidence of dynamic alteration in response to serum in GSCs (supplemental Fig. 1C).…”

Nuclear and cytoplasmic localization of neural stem cell microRNAs

“…Focusing further on differentiation, we note that Letzen et al (2010) reported extensive miRNA profiles for eight stages of differentiation from human embryonic stem cells to terminally differentiated oligodendrocytes. Fortuitously, several miRNAs were assayed in both the Letzen work and in our work.…”

Myelin Gene Regulatory Factor Is Required for Maintenance of Myelin and Mature Oligodendrocyte Identity in the Adult CNS

“…Although it is not yet entirely clear whether the observed dysregulation of MRF in these models is a causal component of the demyelination or merely symptomatic of oligodendrocyte dysfunction and loss, our results support the notion that dysregulation of MRF in NPC1 or other diseases could feasibly have a key role in the ultimate loss of myelin. Although roles for MRF in human myelination have not yet been formally established, it is known that the human ortholog C11Orf9 is enriched in myelin-rich regions of the human brain (Oldham et al, 2008), downregulated in human fetuses with a lethal motor neuron/oligodendrocyte disease (Pakkasjarvi et al, 2005), and upregulated during differentiation of oligodendrocytes from human ES cells (Letzen et al, 2010), suggesting conserved roles in myelination between mice and humans. As such, identification of the mechanisms by which MRF expression is regulated and its roles in human diseases will be an important subject of future work.…”