Effects of Myostatin b Knockout on Offspring Body Length and Skeleton in Yellow Catfish (Pelteobagrus fulvidraco)

Simple SummaryMyostatin is a negative regulator of muscle growth and development, and mutational inactivation of this gene increases muscle mass. Knockout of themstnbgene inPelteobagrus fulvidracodid not increase muscle mass, although our previous study of themstnagene did. Instead, it reduced the body size and growth performance ofPelteobagrus fulvidraco. Through the present study, we found that the mutantPelteobagrus fulvidracohad a reduction in the number of vertebrae, the length, and the intervertebral distance inPelteobagrus fulvidraco, and these changes may be the underlying cause of the shorter body length in mutantPelteobagrus fulvidraco. Histological comparison of the same sites in themstnmutant and wild groups ofPelteobagrus fulvidracoalso revealed that the number and density of osteocytes were greater inmstnbknockoutPelteobagrus fulvidracothan in wild-typePelteobagrus fulvidraco.AbstractBased on obtainingmstnbgene knockout inPelteobagrus fulvidraco, a study on the effect of themstngene on skeletal morphology and growth was performed by comparing the number and length of the vertebrae of mutant and wild-type fish in a sibling group ofP. fulvidraco, combined with the differences in cells at the level of vertebral skeletal tissue. It was found thatmstnbgene knockdown resulted in a reduction in the number of vertebrae, the length, and the intervertebral distance inP. fulvidraco, and these changes may be the underlying cause of the shorter body length in mutantP. fulvidraco. Further, histological comparison of the same sites in themstnmutant and wild groups ofP. fulvidracoalso revealed that the number and density of osteocytes were greater inmstnbknockoutP. fulvidracothan in wild-typeP. fulvidraco. Our results demonstrated that when using genome editing technology to breed new lines, the effects of knockout need to be analyzed comprehensively and may have some unexpected effects due to insufficient study of the function of certain genes.Keywords:myostatin b;genome editing;Pelteobagrus fulvidraco;body length;skeleton;vertebral centrum