Meeting Abstract
Myostatin (MSTN), also known as growth and differentiation factor 8 (GDF8), is a member of the transforming growth factor-β (TGF- β) superfamily. MSTN plays a crucial role in muscle growth, development, and differentiation. Recently, the primitive isoform of MSTN and GDF11 was identified in the shrimp, Litopenaeus vannamei (Liv-MSTN/GDF11). However, result of Liv-MSTN/GDF11 knockdown by dsRNA was different from the case with mammalian MSTN, by which muscle fibers were doubled. Instead, many of them were lethal and even survived shrimp showed significantly lower growth rate compared with those in control group. In present study, we compared transcriptomes between in the tail muscle and in the thoracic muscle after Liv-MSTN/GDF11 dsRNA injection using the Illumina Miseq platform. We screened the genes, whose transcriptional levels changes significantly (> 10 folds) in each tissue. 83 and 122 were identified as the differentially expressed genes between experimental and control groups; 57 and 88 of these genes were down-regulated, 26 and 34 genes were up-regulated in the thoracic and tail muscle. Among the differentially expressed genes after Liv-MSTN dsRNA injection, the transcriptional responses of the several isoforms of myosin heavy chains (MHCs) were different between the thoracic muscle and deep abdominal muscle. This result suggested that Liv-MSTN functions differently in different muscle types and further study should be made to know the biological implications of the different MHC isoforms in muscle growth and development in decapod crustaceans. These finding using the transcriptomic analysis help to understand the molecular mechanisms of muscle growth, development and differentiation.
