Study On TOR Signaling Pathway And Functional Analysis Of Two Important Factors In Litopenaeus Vannamei

The study is about the TOR signaling pathway that is closely related to the cell growth and metabolism in Litopenaeus vannamei.The experiment carried out explored the TOR signaling pathway and will provide theoretical support for the future production of prawns.In order to find the cellular processes regulated by TOR signaling pathway,rapamycin(an inhibitor of TOR signaling pathway)was injected into shrimps,and the gene expression changes analysed by RNAseq.The expression of some genes involved in apoptosis,autophagy,some heat shock protein genes and genes related to function of lysosome and feedback regulation of TOR signaling pathway were found differently expressed.The TOR signaling pathway can be depressed by rapamycin and autophagy were promoted in shrimps.To further explore the autophagy regulatory mechanism,the concentration and phosphorylation of related proteins were analyzed by Western Blot.Phosphorylating of ATG1 can be depressed and dephosphorylating of ATG13 can be promoted by treatment with the rapamycin.The c DNA sequence of rheb from Litopenaeus vannamei was cloned for the first time by RAC E technology.The full lenghth of rheb c DNA sequence is 898 bp,containing an open reading frame of 549 bp that encoded 182 amino acid.It was found that the rheb expressed in all tissues detected,and the expression level of rheb in the intestine was the lowest.Dietary restriction or rapamycin injection could promote the expression of rheb,and the leucine and arginine injection could relieve the accelerated expression of rheb caused by dietary restriction.What's more,rapamycin could totally hinder the regulation of leucine to rheb in shrimp.The expression of raptor,another major factor of TOR signaling pathway,was found promoted by dietary restriction or rapamycin injection.The amino acids could relieve the accelerated expression of raptor caused by dietary restriction and rapamycin injection.In addition,we found the phosphorylation of S6 K and 4EBP were closely related to Raptor.Compared with S6 K,the phosphorylation of 4EBP was more dependent on Raptor.The reports on the molecular mechanisms of nutrition and metabolism in aquatic animals are rare,especially in crustaceans.The results of the study can deepen our understanding of the important signaling pathway in crustaceans and reveal the evolutionary traces of TOR signaling pathway.What's more,the mechanism research can provide more reliable way to select the new breed and optimize the feed formula.