Functional validation and expression analysis of myotubes converted from skin fibroblasts using a simple direct reprogramming strategy

Abstract

Previously, we reported that MyoD, a master gene for myogenic cells, could efficiently convert primary skin fibroblasts into myoblasts and myotubes, thereby effecting direct reprogramming. In this study, we further demonstrated that MyoD-expressing primary fibroblasts displayed rapid movement in culture, with a movement velocity that was significantly faster, almost four times, than mouse primary myoblasts. MyoD-transduced cells obtained the characteristics of Ca2 + release and electrically-stimulated contraction, which was comparable to C2C12 myotubes, suggesting that the essential features of muscle were observed in the transduced cells. Furthermore, the ability to fuse to the host myoblasts means that gene transfer from MyoD-transduced cells to host muscle cells could be obtained by cell fusion. In comparison with the iPS method (indirect reprogramming), our transduction method has a low risk for tumorigenesis and carcinogenesis because the starting cells are fibroblasts and the transduced cells are myoblasts, both normal and mortal cells. Accordingly, MyoD transduction of human skin fibroblasts using the adenoviral vector is a simple, inexpensive and promising candidate as a new cell transplantation therapy for patients with muscular disorders.

Transcription factor induced conversion of human fibroblasts towards the hair cell lineage

“…Given the short period of time required for the conversion process, and the unsuitability of maintaining high levels of expression of the ATOH1 gene, a transient overexpression of the GPA genes should suffice. In this regard, adenoviruses, as well as integrase-defective lentiviral vectors have already yielded successful outcomes [ 62 , 64 , 65 , 66 ]. Furthermore, there are other ways to guide cellular transdifferentiation, such as the introduction of DNA sequences via non-viral methods [ 67 , 68 ], or the use of proteins, microRNAs, RNAs or combinations of small molecules [ 17 , 69 ].…”