Dystrophin is an essential muscle protein that contributes to cell membrane stability by mechanically linking the actin cytoskeleton to the extracellular matrix via an adhesion complex called the dystrophin-glycoprotein complex. The absence or impaired function of dystrophin causes muscular dystrophy. Focal adhesions (FAs) are also mechanosensitive adhesion complexes that connect the cytoskeleton to the extracellular matrix. However, the interplay between dystrophin and FA force transmission has not been investigated. Using a vinculin-based bioluminescent tension sensor, we measured FA tension in transgenic C2C12 myoblasts expressing wild-type (WT) dystrophin, a nonpathogenic single nucleotide polymorphism (SNP) (I232M), or two missense mutations associated with Duchenne (L54R), or Becker muscular dystrophy (L172H). Our data revealed cross talk between dystrophin and FAs, as the expression of WT or I232M dystrophin increased FA tension compared to dystrophin-less nontransgenic myoblasts. In contrast, the expression of L54R or L172H did not increase FA tension, indicating that these disease-causing mutations compromise the mechanical function of dystrophin as an FA allosteric regulator. Decreased FA tension caused by these mutations manifests as defective migration, as well as decreased Yes-associated protein 1 (YAP) activation, possibly by the disruption of the ability of FAs to transmit forces between the extracellular matrix and cytoskeleton. Our results indicate that dystrophin influences FA tension and suggest that dystrophin disease-causing missense mutations may disrupt a cellular tension-sensing pathway in dystrophic skeletal muscle.
|Original language||English (US)|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|State||Published - Jun 21 2022|
Bibliographical noteFunding Information:
ACKNOWLEDGMENTS. We thank Karen Evans for manuscript revision, Polina Alexandrovich for assistance with data compilation, and Yahor Savich for helpful discussion. We acknowledge funding from the NIH (R01AR042423, R01AR049899-J.M.E.; R35GM119483-W.R.G.; U54 CA210190, P01 CA254849, U54 CA268069-D.J.O.) and the Muscular Dystrophy Association. W.R.G. is a Pew Biomedical Scholar. M.P.R. acknowledges funding from the University of Minnesota Frieda M. Kunze and Doctoral Dissertation Fellowships; M.J.M.A. acknowledges the Medical Scientist Training Program (T32GM008244); M.D.K. acknowledges a Cancer Center Training grant (T32CA009138); and L.J.S. acknowledges the National Institute on Aging Training Program for Functional Proteomics of Aging (T32AG029796).
© 2022 the Author(s).
- cell migration
- molecular tension sensors
- muscular dystrophy
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't
- Research Support, N.I.H., Extramural