The Role Of Rbm24 In Mouse Embryonic Stem Cell Derived Skeletal Muscle Differentiation

Skeletal muscle is the most abundant tissue in human body,and is essential for life activities,especially for the maintenance of sports.However,the number of renewable skeletal muscle stem cells in the adult human body is limited,thus it is not sufficient to supplement the damaged muscle cells when the muscle has a relatively large injury or disease.Embryonic stem cells(ESCs)have been a hot spot in the field of tissue and organ regeneration.ESCs can differentiate into skeletal muscle and can be used for regenerative medicine,but the regulatory mechanism remains unclear.Therefore,to study the ESCs derived skeletal muscle differentiation may provide more evidence for the skeletal muscle diseases related cell replacement therapy and drug screening.Rbm24 is highly expressed in skeletal muscle.This study showed there is an increased expression of Rbm24 in the differentiation process of mouse embryonic stem cells,which is accompanied with the expression of myogenic genes.We used Cre-Loxp system to induce the overexpression of Rbm24 in mouse embryonic stem cells,and to explore the role of Rbm24 in ESCs-derived skeletal muscle differentiation.We use hanging drop method to induce ESC differentiation and test the expression of Rbm24 and skeletal muscle specific markers.By real time-RCR,our results showed that compared with the control group,the expressions of Pax3,Pax7 and MyoG increased significantly after over-expression of Rbm24.Immunofluorescence staining showed that the protein level of MyoG and MyHC were also increased significantly.At the day 25 post differentiation,we observed a continuous twitch of skeletal mucscle in Rbm24 overexpression group,which indicates that Rbm24 can promote the differentiation of mouse embryonic stem cells into skeletal muscle.Next,we used C2C12 myoblast cell line to double check the role of Rbm24 in skeletal muscle differentiation.We found that knocking down-Rbm24 can inhibit the differentiation of C2Cl2 into skeletal muscle,whereas overexpressiong Rbm24 can promote the differentiation.These results implicate an essential role of Rbm24 in skeletal muscle differentiation,but the underlying mechanism needs further investigation.