Mechano growth factor (MGF) promotes proliferation and inhibits differentiation of porcine satellite cells (PSCs) by down-regulation of key myogenic transcriptional factors
Authors: De-Lin Mo
Jian Xu
Yao-Sheng Chen
Li-Li Qin
Jia-Qi Li
Xiao-Kui Li
Xiong Tong
Zhe Zhang
Zhi-Cheng Pan
Qiao-Ming Long
Chong Wang
Journal: Molecular and Cellular Biochemistry (2012)
Discipline: MOLECULAR BIOLOGY & GENETICS
Keywords: Porcine satellite cells; mechano growth factor (MGF); proliferation; differentiation; MyoD
Affiliations: College of Animal Science/Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, South China Agricultural University, Guangzhou, Guangdong, People's Republic of China.

Abstract:  Porcine satellite cells represent an ideal model system for studying the cellular and molecular basis regulating myogenic stem cell proliferation and differentiation and for exploring the experimental conditions for myoblast transplantation. Here, we investigated the effects of mechano growth factor (MGF), a spliced variant of the IGF-1 gene, on porcine satellite cells. We show that MGF potently stimulated proliferation while inhibited differentiation of porcine satellite cells. MGF-treatment acutely down-regulates the expression of myogenic determination factor (MyoD) and the cyclin-dependent kinase inhibitor p21. MGF-treatment also markedly reduced the overall expression of cyclin B1 and key factors of the myogenic regulatory and myocyte enhancer families, including Myogenein and MEF2A. Taken together, the gene expression data from MGF-treated porcine satellite cells are in favor of a molecular model in which MGF inhibits porcine satellite cell differentiation by down-regulating either the activity or expression of MyoD, which, in turn, suppresses the expression of key genes required for cell cycle progression and differentiation, such as p21, Myogenin, and MEF2. Overall, our findings are in support of the previous suggestion that MGF may be used in vivo and in vitro to promote proliferation of myogenic stem cells to prevent and treat age-related muscle degenerative diseases. 

Retracted: No

PubPeer comments:
 Figure 2. * In the control row, Day 7 and Day 10 panels appear to look the same, with one of them mirrored. Reported to the journal in October 2015, with a friendly reminder in 2017, but no response as of today. ![file] , 
 We are so sorry that we didn t respond the comments in 2015 and 2017. It seems that this is the first time I got the comments. We will reply it as soon as possible. We need some time to check the original pictures because 8 years has passed since the paper was published. , 
 January 12, 2021 Dear Dr. Bik: Thank you very much for bringing this matter to our attention. You mentioned in your email that you contacted me in 2015 and 2017 but did not receive any response from me. I do not recall receiving any emails from you until now. I have carefully compared the photomicrographs on the 7th day and the 10th day of the porcine satellite cell differentiation after receiving your email. It is indeed that the student made a mistake and confused the pictures on the 7th day and the 10th day. As the corresponding author of this paper, it was my negligence not to discover and correct this error in time. I sincerely apologize for that! The first author Mr. Li-Li Qin graduated almost ten years ago. I contacted him, and he indicated that he has no recollection of what had happened during 2011, and he no longer has any original data in his possession. I have also gone through my records in the past two days but could not find the original photomicrographs. We lost a lot of data in the past ten years due to repeated power outages and computer crashes. I suspect the original data file for this study was among the losses we suffered during one such incidence when we lost a lab computer. Nevertheless, even without the results on day ten did not affect the conclusion that  MGF potently inhibits differentiation of porcine satellite cells in vitro. This conclusion can be drawn with certainty based on the results on day 5 and day 7. I will contact the Molecular and Cellular Biochemistry editor to discuss this matter and identify an appropriate solution. I will keep you informed on the outcome of this matter. Thanks again for pointing out this error! Sincerely, Chong Wang, Ph.D. Professor College of Animal Science South China Agricultural University Wushan Road Tianhe District, Guangzhou, China, 510642 ,