| Hyperglycemic hormone (Crustacean hyperglycemic hormone, CHH) plays an important part incrustacean’s physiological and biochemical processes, such as its growth and development etc. It is not only inthe regulation of a variety of important physiological activities, such as blood glucose, the growth, molting,gonadal development etc., but also can significantly improve the hemolymph glucose concentrations,regulating carbohydrate metabolism crustaceans, performing particularly evidently in the developmental stages.The eyestalk tissue of crustaceans, having most abundant hyperglycemic hormone, has most been studied anda hot research throughout the world.Oratosquilla oratoria is one of the important coastal marine perennial economic crustacean seafood andexcellent wild specie with a very high economic value. In recent years, with increasing efforts to developOratosquilla oratoria, coupled with overfishing, its wildlife resources tendencies to failure has occurred, andtherefore resource protection and appreciation is a serious problem. Research reports on foreign mantis shrimpare more and more, but mainly concentrated in genetic diversity, morphological development, ecology,histology, farming, breeding, etc., while only one, is on analysis of functional gene expression of Oratosquillaoratoria. Searching CHH neuropeptides, we find that evolutionary relationships of crustaceans are stillunknown. CHH in decapod crustacean taxa have done a lot of research work, isopod crustaceans mouth yetrelated research reports. Therefore, it is necessary to meet their counterparts in CHH genetic characteristics toprovide important bases to explore crustacean growth, functional evolution of reproductive genes andevolutionary relationships. This paper orders oratosquilla as experimental materials, Using rapid amplificationof CDNA ends (RACE) method and doing real-time fluorescence quantitative analysis on tissues oforatosquilla oratoriaz, aiming at laying foundations for related functional researches of oratosquilla oratoria’smolting and mechanism of action, meanwhile providing a reference for other crustaceans’ family geneticfunctional studies and evolutionary mechanism.Total RNA in eyestalk of Oratosquilla oratoria was extracted for the first time and cDNA sequence ofcrustacean hyperglycemic homone (CHH) are obtained by RACE method. The result shows that the full lengthof the CHH gene is242bp, containing an180bp5’-untranslated region (UTR), and1821bp3’UTR, and420bpopen reading flame (ORF) which encoded139amino acids. Prediction of protein structure is composed of23.74%α-helix,23.02%extension chain,53.24%random coil, and its molecular mass is15,470Daltons withan estimated pI of7.049.The mature peptide contained six conserved Cys residues in CHH family. TheC-terminus mature peptide was GK which has the same characteristics with ES-CHH. Based on proteinsimilarity comparison, the separated CHH gene was classified into the type I CHH family of peptides.Phylogenetic analysis shows that CHH of O. oratoria and CHH of decapod species formed two subgroups onthe same branch of the tree. These subgroups then clustered with MIH/GIH from decapod species. Expressions of CHH gene in different organizations tested by PCR technology show the tissue specificity, expression wassignificantly higher in the blood, intestine and eyestalk than in the ovary(6000.9and573.7higher,respectively).CHH gene expression was very high in the intestine and brain, but very low in the muscle andovary, and no expression in testis. The results for the further Oratosquilla CHH polypeptide-related functionsand mechanism of action studies lay the foundation, but also provide a reference for other crustaceans CHHgene research and system evolution and classification systems. |
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