| Abstract: | Raptor, a member of the target of rapamycin complex 1 (TORC1), participates in the formation of complex proteins related to the mechanistic target of rapamycin (mTOR) signalling. In this study, a 5,020 bp cDNA of Raptor with an open reading frame (ORF) of 3,804 bp encoding for 1,267 amino acids was cloned from Litopenaeus vannamei. The protein contains three conserved domains: Raptor N, HEAT and WD40 domains. The expression of Raptor gene was detected by qRT‐PCR in different tissues of L. vannamei, including hepatopancreas, intestinal, stomach, eyestalk, gill and muscle. The mRNA expression profiles of Raptor in muscle were also analysed under suppression or stimulation of mTOR signalling pathway. The level of Raptor mRNA significantly increased either at 0.5–6 hr after an injection of rapamycin (RAPA) or after 3 days starvation. Leucine or arginine alleviated the up‐regulation of Raptor gene expression caused by RAPA or starvation. The Raptor gene was successfully suppressed using RNA interference (RNAi) technology, and the gene expression and the protein phosphorylation level of 4EBP1 and S6K were significantly decreased. The results of the study suggested that the expression of Raptor was sensitive to the immunology status of L. vannamei and participated in nutritional metabolism. |
