The Structure Of Striped Hamsters Ot/otr Analysis And Study Of Differentially Expressed

Striped hamster （Cricetulus barabensis） becomes one of the dominant species thatthreatened the production and living of human as its high reproduction and the ability to adapt toenvironment,so it is important to study the genes that may influence its reproduction.Oxytocin(OT) is known as the gene which has close relationship with reproduction,it is not onlyassociated with delivery and milk ejection but also affects the spouse selection and aggressivebehaviour.Besides, oxytocin must bind to its receptor(OTR) and then could play itsroles.Therefore,cDNA of OT and OTR in Cricetulus barabensis were cloned and analyzed in thisstudy to forecast the molecular structures of OT and OTR,and then expression of OT and OTR indifferent developmental stages and tissues for Cricetulus barabensis were compared to forecastthe functions that OT expressed in growth,development and reproduction for Cricetulusbarabensis.In these ways,the effective methods from the biological point of views could befound to control the population and harmfulness of Cricetulus barabensis.In this research,the Cricetulus barabensis captured in the Wucun of Qufu and Yinan ofLinyi in Shandong Province were used to clone the cDNA of OT and OTR by RT-PCRtechnique,as a result,314bp of OT (GenBank accession: JQ416144)and442bp of OTR (GenBankaccession: JN180665) was obtained.A variety of molecular biology software were used toforecast and analyze the second structures and tertiary structures of the two proteins.C-Y-I-Q-N-C-P-L-G in coding regions of OT constitute the matured OT,a disulfide linkage isformulated between the two Cys that located in the first and sixth site,the amino acid residuesafter the nine develop into transporting protein.Then, tertiary structure of transporting proteinwas forecasting by using the protein homology modeling server which is calledSWISS-MODEL.As for OTR,the sequences contain the second,the third,the forth and a part ofthe fifth transmembrane helix. We inferred that the extracellular domain before the secondtransmembrane helix was associated with the binding to C-terminus of OT,the latter extracellulardomain was contributed to recognizing about annulation of OT,the third and the forthtransmembrane helix may also participated in the process of recognizing.Besides,a potentialphosphorylation site and a disulfide linkage were found in this sequence,the four successive “L”played an important role in stablilize3D structure of OTR.And then partial of tertiary structuresof OTR were calculated by SWISS-MODEL. The partial cDNA sequence of OT and OTR inCricetulus barabensis were separately compared with the corresponding sequences of Rattusnorvegicus, Mus musculus, Homo sapiens,etc. and the phylogentic trees were structured. Resultshowed that, the genetic relationships among Cricetulus barabensis, Mesocricetus auratus and Microtus ochrogaster was closest,after that were Rattus norvegicus and Mus musculus, thegenetic relationships among Cricetulus barabensis,animals of Primates and cloven order werefarther.After that,relative expression of OT and OTR for Cricetulus barabensis were comparedseparately in different developmental stages and tissues through the technology of real-timefluorescent quantitative PCR. The developmental stages were minor, oestrum,aged and thetissues were brain,heart,reproductive organ.The findings discovered OT expressed primarily inthe brain,while OTR expressed primarily in the peripheral organs.So we deemed that OT wasproduced in the brain，but took effect in the peripheral organs. The high expression of OT in thebrain and ovary in oestrum implied that OT has impact in oestrus of Cricetulus barabensis for acertain extent. In the female reproductive organs,especially in uterus,the expression of OT inoestrum and aged individuals was far above its in minor.This indirectly indicated that thedevelopment of uterus in minor stage has not yet completely,so maybe we could make sure theexact developmental stages about oestrus and reproduction for female by measuring expressionof hormone.Besides,the results showed that the expression of OT and OTR in the heart of minorindividuals were a little high,and also presumably,OT was evolved in connection with thedevelopment and functions of heart though mechanism needed further research.On the whole,thedifferent expression of OTR much more on account of differences caused by organs than bydevelopmental stages,but for OT among special organs and specific developmental period,thedistinction of expression were obvious.In conclusion,research for OT could not be restricted toits molecular structure and expression,integrated study of it with other related genes such as OTRis really demanded.