In vitro expression and functional characterization of NPA motifs in aquaporins of Nosema bombycis
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Nosema bombycis contains functional aquaporins (NbAQPs), which are key targets for exploring the mechanism of N. bombycis infection; however, the regulation of these NbAQPs remains unknown. The two highly conserved asparagine-proline-alanine sequences (NPA motifs) play important roles in AQP biogenesis. As part of this study, we constructed a series of NbAQP mutants (NbAQP_NPA1, NbAQP_NPA2, and NbAQP_NPA1,2) and expressed them in BmN cells. The results showed that mutations in either NPA motif or in both NPA motifs did not affect NbAQP expression in vitro. After expression in Xenopus laevis oocytes, those injected with wild-type NbAQP rapidly expanded, whereas oocytes injected with NbAQP_NPAs did not significantly change in size. The associated water permeability (pf) of NbAQP_NPAs was significantly reduced five–six times compared to that of wild-type NbAQP. These results indicated that NPA motifs are necessary for the water channel function of AQPs in N. bombycis. The present study shows for the first time that the NbAQP NPA motif has an impact on the water permeability of aquaporin in N. bombycis, thereby providing a platform for further research into the mechanisms underlying the regulation of NbAQP expression.
KeywordsNosema bombycis Aquaporin NPA motifs Immunofluorescence Water permeability
This work was supported by the earmarked fund for the China Agriculture Research System and the National Natural Science Foundation of China (Grant No. 31372376).
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Conflict of interest
The authors declare that have no conflicts of interest.
- Rambow J, Wu B, Rönfeldt D, Beitz E (2014) Aquaporins with anion/monocarboxylate permeability: mechanisms, relevance for pathogen–host interactions. Front Pharmacol 5(199). https://doi.org/10.3389/fphar.2014.00199
- Schrade K, Tröger J, Eldahshan A, Zühlke K, Abdul Azeez KR, Elkins JM, Neuenschwander M, Oder A, Elkewedi M, Jaksch S, Andrae K, Li J, Fernandes J, Müller PM, Grunwald S, Marino SF, Vukićević T, Eichhorst J, Wiesner B, Weber M, Kapiloff M, Rocks O, Daumke O, Wieland T, Knapp S, von Kries JP, Klussmann E (2018) An AKAP-Lbc-RhoA interaction inhibitor promotes the translocation of aquaporin-2 to the plasma membrane of renal collecting duct principal cells. PLoS One 13(1):e0191423CrossRefGoogle Scholar
- Undeen AH (1983) The germination of Vavraia culicis spores. J Eukaryot Microbiol 30(2):274–277Google Scholar