Study On The Aquaporins Genes Of Echinococcus Multilocularis

Objective To analyze the sequences and structural characteristics of Echinococcus multilocularis Aquaporins?EmAQPs?,as well as assay their water channel activities in Xenopus laevis?X.laevis?oocytes,providing a foundation to explore the function of EmAQPs during the formation of cyst fluid.Methods The sequences and structural characteristics of Em AQPs were analyzed by bioinformatic methods.The total RNA was extracted from alveolar hydatid cyst,the CDS sequences of Echinococcus multilocularis?E.multiloculars?were cloned by RT-PCR with specific primers,the expression vector of EmAQPs were constructed by subcloning the objective DNA fragment into pCS-107,and the water channel activities of EmAQPs were assayed in X.laevis oocytes.Results1.The results of bioinformatic analysis indicated EmAQPs belonged to MIP superfamily,which could selectively transport water and small solutesacross plasma membranes.The transmembrane regions of EmAQPs ranged from two to five and only EmAQP9?accession number: CDS35949.1?contained two conserved NPA boxes.A neighbor-joining tree indicated that EmAQPs were divided into two branches,four Em AQPs form a clade with AQP1 of homo sapiens,a “strict” aquaporin,other two Em AQPs form a clade with AQP9 of homo sapiens,an aquaglyceroporins.The similarity between EmAQPs and AOPs of homo sapiens ranged from 27% to 43%.2.Six coding genes of AQPs were found in the genome of E.multiloculars,but only EmAQP4?accession number: EmuJ₀00124900?and EmAQP9?accession number: EmuJ₀01190800?were isolated successfully.The recombinant plasmids pCS-107-EmAQP4 and pCS-107-EmAQP9 were constructed.EmAQP4 and EmAQP9 were heterogeneously expressed in X.laevis oocyte.Unfortunately,EmAQP4?accession number: EmuJ₀00124900?and EmAQP9?accession number:EmuJ₀01190800?could not perform their water channel activities in X.laevis oocyte.Conclusion In this study,EmAQP4 and EmAQP9 were isolated successfully but could not perform their water channel activities in X.laevis oocyte,which might be resulted from the differences of the protein structure between Em AQPs and “strict” aquaporin.Water could't be transported through EmAQPs and caused vesicle lysis,so the vesicles of E.multiloculars could survive for a long time in the organs or tissues of theintermediate hosts.The similarity between EmAQPs and AOPs of homo sapiens ranged from 27% to 43%,which indicated that EmAQPs might be attractive targets for drug treatment of alveolar echinococcosis.These results suggested that the alveolar cysts of E.multiloculars could be destroyed by water inflow or antiparasitic drugs transported through the water channels if EmAQPs activators were found,which provided a foundation to screen for new therapeutical drug targets for AE.