Abstract
Regulation of gene expression is critical for the maintenance of cell state and homeostasis. Aberrant regulation of genes can lead to unwanted cell proliferation or misdirected differentiation. Here we investigate the role of MED31, a highly conserved subunit of the Mediator complex, to determine the role this subunit plays in the maintenance of human mesenchymal stem cell (hMSC) state. Using siRNA-mediated knockdown of MED31 we demonstrate a decrease in self-renewal based on cell assays and monitoring of gene expression. In addition, in the absence of MED31, hMSCs also displayed a reduction in adipogenesis as evidenced by diminished lipid vesicle formation and expression of specific adipogenic markers. These data present evidence for a significant role for MED31 in maintaining adult stem cell homeostasis, thereby introducing potential novel targets for future investigation and use in better understanding stem cell behavior and adipogenesis.
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Acknowledgements
We would like to thank Dr. Bruce Bunnell and his lab for supplying and supporting training in the culturing and characterization of human mesenchymal stem cells. We thank the Research Core Facility Genomics Core at LSU Health Shreveport, which is supported in part by the Center for Cardiovascular Diseases and Sciences, the Center for Molecular and Tumor Virology, and the Feist-Weiller Cancer Center, for their assistance with microarray hybridization, scanning, and initial data analysis. We would like to acknowledge funding support for this project from the Louisiana Biomedical Research Network, an NIH INBRE grant (8P20GM103424), Louisiana Board of Regents Pilot Funding Program, and Louisiana Tech University College of Applied and Natural Sciences and School of Biological Sciences for support of students and purchasing of supplies. Finally, we would like to thank Matthew Busby and Michael Osmun for their help with primer optimization and preliminary data collection.
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The GEO accession no is GSE116973 and the link for the GEO dataset to be referenced in the manuscript is as follows: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE116973.
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Beadle, E.P., Straub, J.A., Bunnell, B.A. et al. MED31 involved in regulating self-renewal and adipogenesis of human mesenchymal stem cells. Mol Biol Rep 45, 1545–1550 (2018). https://doi.org/10.1007/s11033-018-4241-5
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DOI: https://doi.org/10.1007/s11033-018-4241-5