Damaged muscle regenerated by protien cdk9-55
5 July 2008
A new understanding of the role played by the protein cdk9-55 in
muscle regeneration and differentiation may lead to novel therapies to
rebuild muscle tissue damaged by disease, injury and aging, according to
researchers at the Sbarro Institute for Cancer Research and Molecular
Medicine at Temple University in Philadelphia and the University of
The researchers was reported in the Journal of Cellular Physiology
Adult skeletal muscle tissue can regenerate in response to direct
injury, neurological dysfunction and genetic defects. This healing
process begins with an activation of muscle stem cells, known as
satellite cells. Once activated, the satellite cells multiply and then
differentiate into specific types of muscle fibres that eventually fuse
to reconstitute muscle tissue.
The researchers discovered that cdk9-55, a variation of the gene
cdk9, is induced specifically when satellite cells begin differentiation
and is necessary for the genetic reprogramming required to complete the
muscle tissue regeneration process.
"By administering cdk9-55 or a protein encoded by a cdk9-55 gene
directly to the muscle or on a resorbable material applied to injured or
diseased muscle tissue or to an area missing muscle tissue, we can
regenerate muscle," said lead researcher Cristina Giacinti, a researcher
at the Sbarro Institute and the Department of Histology and Medical
Embryology, University of Rome, Italy.
Researchers also found that cdk9-55 can be used to increase muscle
tissues in healthy tissue.
"This discovery has important implications for tissue regeneration in
muscle tissue damaged by disease and injury, genetic disorders such as
muscular dystrophy, chronic disorders like cancer or HIV that may impair
muscle regeneration, and diseases related to aging," said Dr Antonio
Giordano, Director of the Sbarro Institute.
1. Cdk9-55: A New Player in Muscle Regeneration. Journal of