基于转录组分析对中国对虾Myostatin基因调控的肌肉生长相关基因的筛选

Screening of Genes Related to Muscle Growth under the Myostatin Regulation by RNA-Seq in Fenneropenaeus chinensis

Myostatin(Mstn)即肌肉生长抑制素,在脊椎动物中是胚胎期肌肉形成和成体肌肉生长的主要调控因子之一,通过抑制肌细胞的扩增和分化而抑制肌肉的生长和发育。为了筛选在中国对虾(Fenneropenaeus chinensis)中Mstn调控的肌肉生长相关的基因,为肌肉生长调控机理奠定基础,本研究利用RNA-Seq技术对PBS对照组和Mstn表达抑制组进行了测序分析。结果显示,Mstn表达被抑制后,共筛选到1657个差异表达基因,其中,805个显著上调,852个显著下调。参考脊椎动物Mstn调控的肌肉生长经典信号通路TGF-β/Smad和MAPK通路及差异基因功能已有报道,初步筛选出29个Mstn调控的与肌肉生长相关的基因。在涉及TGF-β/Smad和MAPK通路的16个基因中,除ActRI被检测到略微上调外,其他基因均表现出不同程度的下调;在另外13个涉及蜕皮、肌肉生长等过程的基因中,促进肌肉生长的基因显示为上调。前期的研究表明,Mstn可能同脊椎动物功能类似,在中国对虾中负向调控肌肉生长,而本研究结果提供了进一步的证据,为阐明对虾的肌肉发育调控机制提供了重要基础。

Myostatin(Mstn)is one of the main regulatory factors of embryonic muscle formation and adult muscle growth in vertebrates,which inhibits muscle growth and development by inhibiting the expansion and differentiation of muscle cells.Our previous researches have preliminarily suggested that Mstn involved in myogenesis and muscle growth probably as a negative regulator in Fenneropenaeus chinensis like vertebrates.In order to screen genes related to muscle growth regulated by Mstn in F.chinensis and understand the mechanism of muscle growth regulation,RNA-Seq technology was used to sequence control group injected PBS and experimental group injected siRNA for inhibition of Mstn expression.The results showed that a total of 36,605 unigenes were produced and 19,628 genes were annotated by transcriptome analysis.Under the inhibition of Mstn expression by RNAi,a total of 1657 differentially expressed genes were screened,of which 805 genes were significantly up regulated and 852 genes were significantly down regulated.Referring to the previous reports of TGF-β/Smad and MAPK pathways as well as function of differential genes,29 genes related to muscle growth regulated by Mstn were preliminarily screened.In these genes,16 genes were involved in TGF-β/Smad and Mapk pathways.Among the 16 genes,only the ActRI was detected to be slightly up-regulated and other genes showed different degrees of down-regulation.The other screened 13 genes were involved in molting,muscle growth and other processes related muscle such as muscle contractions,of which the genes correlated with promoting muscle growth were detected up-regulation.The results of this study provided further evidence for our previous studies that Mstn probably negatively regulates muscle growth in a similar way to vertebrate in F.chinensis.Our results will also provide important theoretical basis for the regulation mechanism of muscle development in invertebrate.