Piedmontese Myostatin gene – now I really am confused!

Below is an article I read about the unique Myostatin gene found in Piedmontese.  This mutation gives extra muscling, tenderness and healthiness.  If you read the article would you have understood this?  I wouldn’t have!

Courtesy of  http://7thspace.com/

 The C313Y Piedmontese mutation decreases myostatin covalent dimerisation and stability

Myostatin is a key negative regulator of muscle growth and development, whose activity has important implications for the treatment of muscle wastage disorders. Piedmontese cattle display a double-muscled phenotype associated with the expression of C313Y mutant myostatin.

In vivo, C313Y myostatin is proteolytically processed, exported and circulated extracellularly but fails to correctly regulate muscle growth. The C313Y mutation removes the C313-containing disulphide bond, an integral part of the characteristic TGF-beta cystine-knot structural motif. 

Results: Here we present in vitro analysis of the structure and stability of the C313Y myostatin protein that reveals significantly decreased covalent dimerisation for C313Y myostatin accompanied by a loss of structural stability compared to wild type.

The C313Y myostatin growth factor, processed from full length precursor protein, fails to inhibit C2C12 myoblast proliferation in contrast to wild type myostatin. Although structural modeling shows the substitution of tyrosine causes structural perturbation, biochemical analysis of additional disulphide mutants, C313A and C374A, indicates that an intact cystine-knot motif is a major determinant in myostatin growth factor stability and covalent dimerisation. 

Conclusions: This research shows that the cystine-knot structure is important for myostatin dimerisation and stability, and that disruption of this structural motif perturbs myostatin signaling.

Author: Carlene StarckAndrew Sutherland-Smith
Credits/Source: BMC Research Notes 2011, 4:442