TY - JOUR
T1 - Inhibition of Drp1-dependent mitochondrial division impairs myogenic differentiation
AU - Kim, Boa
AU - Kim, Ji Seok
AU - Yoon, Yisang
AU - Santiago, Mayra C.
AU - Brown, Michael D.
AU - Park, Joon Young
PY - 2013/10/15
Y1 - 2013/10/15
N2 - Mitochondria are dynamic organelles forming a tubular network that is continuously fusing and dividing to control their morphology and functions. Recent literature has shed new light on a potential link between the dynamic behavior of mitochondria and muscle development. In this study, we investigate the role of mitochondrial fission factor dynamin-related protein 1 (Drp1) in myogenic differentiation. We found that differentiation of C2C12 myoblasts induced by serum starvation was accompanied by a gradual increase in Drp1 protein expression (to ~350% up to 3 days) and a fast reduction of Drp1 phosphorylation at Ser-637 (to ~30%) resulting in translocation of Drp1 protein from the cytosol to mitochondria. During differentiation, treatment of myoblasts with mitochondrial division inhibitor (mdivi-1), a specific inhibitor of Drp1 GTPase activity, caused extensive formation of elongated mitochondria, which coincided with increased apoptosis evidenced by both enhanced caspase-3 activity and increased number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Furthermore, the mdivi-1 -treated myotubes (day 3 in differentiation media) showed a reduction in mitochondrial DNA content, mitochondrial mass, and membrane potential in a dose-dependent manner indicating defects in mitochondrial biogenesis during myogenic differentiation. Most interestingly, mdivi-1 treatment significantly suppressed myotube formation in both C2C12 cells and primary myoblasts. Likewise, stable overexpression of a dominant negative mutant Drp1 (K38A) dramatically reduced myogenic differentiation. These data suggest that Drp-1-dependent mitochondrial division is a necessary step for successful myogenic differentiation, and perturbation of mitochondrial dynamics hinders normal mitochondrial adaptations during muscle development. Therefore, in the present study, we report a novel physiological role of mitochondrial dynamics in myogenic differentiation.
AB - Mitochondria are dynamic organelles forming a tubular network that is continuously fusing and dividing to control their morphology and functions. Recent literature has shed new light on a potential link between the dynamic behavior of mitochondria and muscle development. In this study, we investigate the role of mitochondrial fission factor dynamin-related protein 1 (Drp1) in myogenic differentiation. We found that differentiation of C2C12 myoblasts induced by serum starvation was accompanied by a gradual increase in Drp1 protein expression (to ~350% up to 3 days) and a fast reduction of Drp1 phosphorylation at Ser-637 (to ~30%) resulting in translocation of Drp1 protein from the cytosol to mitochondria. During differentiation, treatment of myoblasts with mitochondrial division inhibitor (mdivi-1), a specific inhibitor of Drp1 GTPase activity, caused extensive formation of elongated mitochondria, which coincided with increased apoptosis evidenced by both enhanced caspase-3 activity and increased number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Furthermore, the mdivi-1 -treated myotubes (day 3 in differentiation media) showed a reduction in mitochondrial DNA content, mitochondrial mass, and membrane potential in a dose-dependent manner indicating defects in mitochondrial biogenesis during myogenic differentiation. Most interestingly, mdivi-1 treatment significantly suppressed myotube formation in both C2C12 cells and primary myoblasts. Likewise, stable overexpression of a dominant negative mutant Drp1 (K38A) dramatically reduced myogenic differentiation. These data suggest that Drp-1-dependent mitochondrial division is a necessary step for successful myogenic differentiation, and perturbation of mitochondrial dynamics hinders normal mitochondrial adaptations during muscle development. Therefore, in the present study, we report a novel physiological role of mitochondrial dynamics in myogenic differentiation.
KW - Dynamin-related protein 1
KW - Mdivi-1
KW - Mitochondrial dynamics
KW - Myogenesis
UR - http://www.scopus.com/inward/record.url?scp=84885675007&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84885675007&partnerID=8YFLogxK
U2 - 10.1152/ajpregu.00502.2012
DO - 10.1152/ajpregu.00502.2012
M3 - Article
C2 - 23904108
AN - SCOPUS:84885675007
SN - 0363-6119
VL - 305
SP - R927-R938
JO - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
JF - American Journal of Physiology - Regulatory Integrative and Comparative Physiology
IS - 8
ER -