Myogenic factor 6 (herculin) is a protein that in humans is encoded by the MYF6 gene.
[1]
Also known in the medical literature as MRF4 and herculin), MYF6 is a myogenic regulatory factor (MRF) in the process known as myogenesis.[2][3]
MYF6 is a member of the myogenic factors (MYF) family that regulate myogenesis and muscle regeneration. Myogenics factor are basic helix-loop-helix (bHLH) transcription factors.
MYF-6 is a gene that encodes a protein involved in the regulation of myogenesis. Specifically, it induces the maturation of myotubes into myofibers. The portion of the protein integral to myogenesis regulation is a basic helix-loop-helix (bHLH) domain that is conserved among all of the genes in the MRF family.
MYF-6 is expressed exclusively in skeletal muscle, and it is expressed at a higher levels in adult skeletal muscle than all of the other genes in the muscle regulatory factor factor gene family. MYF-6 is different from the other myogenic regulatory factor genes due to its two-phase expression. Initially, MYF-6 is transiently expressed along with MYF-5 in the somites during the early stages of myogenesis.[4] However, it is primarily expressed postnatally. This suggests that it serves an important role in the maintenance and repair of adult skeletal muscle.[4] The role of MYF-6 expression in the somites during embryogenesis is currently unknown.
The MYF-6 gene is physically linked to the MYF-5 gene on chromosome 12, and mutations in the MYF-6 gene typically exhibit reduced levels of MYF-5.[5] Despite reductions in muscle mass of the back, MYF6 mutants still exhibit fairly normal skeletal muscle. While this demonstrates that MYF-6 might not be essential for the formation of myofibers, it is thought that myogenin compensates for the absence of functional MYF-6.[6]
↑Cupelli L, Renault B, Leblanc-Straceski J, Banks A, Ward D, Kucherlapati RS, Krauter K (1996). "Assignment of the human myogenic factors 5 and 6 (MYF5, MYF6) gene cluster to 12q21 by in situ hybridization and physical mapping of the locus between D12S350 and D12S106". Cytogenet. Cell Genet. 72 (2–3): 250–1. doi:10.1159/000134201. PMID8978788.
↑ 4.04.1Moretti, I. et al. MRF4 negatively regulates adult skeletal muscle growth by repressing MEF2 activity. Nat. Commun. 7:12397 doi: 10.1038/ncomms12397 (2016).
↑Arnold, H. H.; Braun, T. (1996-02-01). "Targeted inactivation of myogenic factor genes reveals their role during mouse myogenesis: a review". The International Journal of Developmental Biology. 40 (1): 345–353. ISSN0214-6282. PMID8735947.
↑Miner J. H. & Wold B. Herculin, a fourth member of the MyoD family of myogenic regulatory genes. Proc Natl Acad Sci USA 87, 1089–1093 (1990)
↑Kerst B, Mennerich D, Schuelke M, Stoltenburg-Didinger G, von Moers A, Gossrau R, van Landeghem FK, Speer A, Braun T, Hübner C (December 2000). "Heterozygous myogenic factor 6 mutation associated with myopathy and severe course of Becker muscular dystrophy". Neuromuscul. Disord. 10 (8): 572–7. doi:10.1016/S0960-8966(00)00150-4. PMID11053684.
Langlands, K.; Yin, X.; Anand, G.; Prochownik, E. V. (1997). "Differential interactions of Id proteins with basic-helix-loop-helix transcription factors". The Journal of Biological Chemistry. 272 (32): 19785–19793. doi:10.1074/jbc.272.32.19785. PMID9242638.
Onions, J.; Hermann, S.; Grundström, T. (2000). "A novel type of calmodulin interaction in the inhibition of basic helix-loop-helix transcription factors". Biochemistry. 39 (15): 4366–4374. doi:10.1021/bi992533u. PMID10757985.
Cupelli, L.; Renault, B.; Leblanc-Straceski, J.; Banks, A.; Ward, D.; Kucherlapati, R. S.; Krauter, K. (1996). "Assignment of the human myogenic factors 5 and 6 (MYF5, MYF6) gene cluster to 12q21 by in situ hybridization and physical mapping of the locus between D12S350 and D12S106". Cytogenetics and Cell Genetics. 72 (2–3): 250–251. doi:10.1159/000134201. PMID8978788.
Kosek, D. J.; Kim, J. S.; Petrella, J. K.; Cross, J. M.; Bamman, M. M. (2006). "Efficacy of 3 days/wk resistance training on myofiber hypertrophy and myogenic mechanisms in young vs. Older adults". Journal of Applied Physiology. 101 (2): 531–544. doi:10.1152/japplphysiol.01474.2005. PMID16614355.
