A missense mutation in ISPD contributes to maintain muscle fiber stability

Livestock and poultry skeletal muscle development was regulated by a variety of genetic factors playing an essential role in this process. In our de novo sequencing, a missense mutation in ISPD exon 2 showed a selected signature for well-developed muscles. However, the relationship between this mutation and muscle phenotypes remains unclear.

Based on the genotype bias of this missense mutation in gamecock chickens, we compared the cross-section of muscle fibers among the individuals with different genotypes with the results showing a genotype preference of this missense mutation in the chickens with hypertrophic muscle fibers. Comparing TT- and CC-genotype ISPD showed that TT- genotype was associated with heavier skeletal muscle and a better effect on myogenesis and myofiber stability. At cellular level, ISPD was identified to inhibit myoblast proliferation, differentiation and antagonize of muscular atrophy.

It can be concluded that the missense mutation of Arg84Lys in ISPD was associated with well-developed muscles and demonstrated to improve chicken muscles' development.