Organ-specific splice variants of aquaporin water channel AgAQP1 in the malaria vector Anopheles gambiae.
BACKGROUND
Aquaporin (AQP) water channels are important for water homeostasis in all organisms. Malaria transmission is dependent on Anopheles mosquitoes. Water balance is a major factor influencing mosquito survival, which may indirectly affect pathogen transmission.


RESULTS
We obtained full-length mRNA sequences for Anopheles gambiae aquaporin 1 (AgAQP1) and identified two splice variants for the gene. In vitro expression analysis showed that both variants transported water and were inhibited by Hg(2+). One splice variant (AgAQP1A) was exclusively expressed in adult female ovaries indicating a function in mosquito reproduction. The other splice variant (AgAQP1B) was expressed in the midgut, malpighian tubules and the head in adult mosquitoes. Immunolabeling showed that in malpighian tubules, AgAQP1 is expressed in principal cells in the proximal portion and in stellate cells in the distal portion. Moreover, AgAQP1 is expressed in Johnston's organ (the "ear"), which is important for courtship behavior.


CONCLUSIONS
These results suggest that AgAQP1 may play roles associated with mating (courtship) and reproduction in addition to water homeostasis in this important African malaria vector.
Department of Entomology, Center for Infectious Disease Dynamics and the Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, Pennsylvania, United States of America.
Hitoshi
H
Tsujimoto
Kun
K
Liu
Paul J
PJ
Linser
Peter
P
Agre
Jason L
JL
Rasgon
D017398:Alternative Splicing; D000818:Animals; D000852:Anopheles / Q000378:metabolism*; D020346:Aquaporins / Q000235:genetics / Q000378:metabolism*; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D007303:Insect Vectors; D008288:Malaria / Q000635:transmission
D020346:Aquaporins; D019476:Insect Proteins