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dc.contributor.advisorPetzel, David H.en_US
dc.contributor.authorHart, Steven J.en_US
dc.date.accessioned2015-03-23T21:44:33Z
dc.date.available2015-03-23T21:44:33Z
dc.date.issued2002en_US
dc.identifier.urihttp://hdl.handle.net/10504/66701
dc.description.abstractA Na+/H+ exchanger (NHE) on the apical membrane of mosquito Malpighian tubule (MT) cells likely participates in the female blood-feeding mosquito's necessary secretion ofNa+ and fluid. This study presents the molecular cloning, primary structure, and tissue distribution of two cDNAs encoding Aedes aegypti mosquito Malpighian tubule NHEs. The cDNA sequences were obtained from mosquito MT total RNA using reverse transcriptase-polymerase chain reaction (RT-PCR) and 5' and 3' rapid amplification of cDNA ends (RACE). The two sequences encode proteins of 678 and 1179 amino acids with calculated molecular weights of 74,473 and 130,276 respectively. When comparing the 678 amino acid protein to the Erst 678 amino acids of the other protein, the two clones show 98% identity to each other. They also exhibit high identity to three Drcosophila melanogaster NHEs in addition to many NHEs from other species. Hydropathy analysis reveals that while both clones have the usual 10-13 transmembrane segments, the 1179 amino acid protein has an extensive carboxy terminus while the 678 amino acid protein has an extremely short carboxy terminus. Various regulatory functions have been attributed to the carboxy terminus and thus its truncation is likely to have profound effects. RT-PCR analysis shows that both clones are expressed in the mosquito Malpighian tubules at the larval, pupal, and adult stages. Their expression was also detected in mosquito ovaries, midguts, and hindguts. The amiloride-binding region is a hallmark of a NHE as amiloride and its analogs are potent inhibitors of NaVH^ exchange. The amiloride-binding regions of the Aedes clones are identical to the amiloride-binding regions of three Drosophila NHEs, 80% identical to the human, rat, and rabbit NHE3s, and 60% identical to the human, rat, and rabbit NHE Is. When comparing the complete amino acid sequences, the mosquito clones show the highest identity to the mammalian NHE3 isoforms. The NHE3 isolbrm is generally most predominant in the brush border of the kidney and GI tract. The functions of the mosquito Malpighian tubules are most similar to the functions of the mammalian kidney, as the Malpighian tubules are vital for maintaining the ionic homeostasis of the hemolymph through secretion of fluid and Na^ and K ions ingested in a blood meal. The two mosquito MT NHEs presented here are likely MT apical membrane NHEs that are vital in meeting mosquito MT secretion requirements.en_US
dc.language.isoen_USen_US
dc.publisherCreighton Universityen_US
dc.rightsCopyright is retained by the Author. A non-exclusive distribution right is granted to Creighton University and to ProQuest following the publishing model selected above.en_US
dc.subject.meshAedes--geneticsen_US
dc.titleCloning and Tissue Distribution of Two NA+/H+ Exchangers from the Malpighian Tubules of Aedes Aegyptien_US
dc.typeThesis
dc.rights.holderSteven J. Harten_US
dc.publisher.locationOmaha, Nebraskaen_US
dc.description.noteProQuest Traditional Publishing Optionen_US
dc.description.pagesix, 78 pagesen_US
dc.contributor.cuauthorHart, Steven J.en_US
dc.degree.levelMS (Master of Science)en_US
dc.degree.disciplineBiomedical Sciences (graduate program)en_US
dc.degree.nameM.S. in Biomedical Sciencesen_US
dc.degree.grantorGraduate Schoolen_US
dc.degree.committeeBrauer, Philip R.en_US
dc.degree.committeeKnezetic, Joseph A.en_US
dc.degree.committeeSmith, D. Daviden_US


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