Phylogenomic and functional analyses of salmon lice aquaporins uncover the molecular diversity of the superfamily in Arthropoda

BMC Genomics

Research Article

Joan Cerd๠ Heidi Kongshaug²  Jon Anders Stavang²  Frank Nilsen²  Francois Chauvigné³  Roderick Nigel Finn⁴ 

[1] Institut de Recerca i Tecnologia Agroalimentàries (IRTA)-Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), 08003, Barcelona, Spain;Sea Lice Research Centre, Department of Biology, Bergen High Technology Centre, University of Bergen, 5020, Bergen, Norway;Sea Lice Research Centre, Department of Biology, Bergen High Technology Centre, University of Bergen, 5020, Bergen, Norway;Institut de Recerca i Tecnologia Agroalimentàries (IRTA)-Institut de Ciències del Mar, Consejo Superior de Investigaciones Científicas (CSIC), 08003, Barcelona, Spain;Sea Lice Research Centre, Department of Biology, Bergen High Technology Centre, University of Bergen, 5020, Bergen, Norway;Institute of Marine Research, Nordnes, 5817, Bergen, Norway;

关键词: Aquaporin;    Aquaglyceroporin;    Arthropod;    Crustacea;    Copepod;    Salmon louse;    Lepeoptheirus;    Parasite;    Atlantic salmon;    Evolution;    Osmoregulation;    Fluid homeostasis;    Permeability;    Selectivity;   

DOI  :  10.1186/s12864-015-1814-8

 received in 2015-03-31, accepted in 2015-08-03,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundAn emerging field in biomedical research is focusing on the roles of aquaporin water channels in parasites that cause debilitating or lethal diseases to their vertebrate hosts. The primary vectorial agents are hematophagous arthropods, including mosquitoes, flies, ticks and lice, however very little is known concerning the functional diversity of aquaporins in non-insect members of the Arthropoda. Here we conducted phylogenomic and functional analyses of aquaporins in the salmon louse, a marine ectoparasitic copepod that feeds on the skin and body fluids of salmonids, and used the primary structures of the isolated channels to uncover the genomic repertoires in Arthropoda.ResultsGenomic screening identified 7 aquaporin paralogs in the louse in contrast to 42 in its host the Atlantic salmon. Phylogenetic inference of the louse nucleotides and proteins in relation to orthologs identified in Chelicerata, Myriapoda, Crustacea and Hexapoda revealed that the arthropod aquaporin superfamily can be classified into three major grades (1) classical aquaporins including Big brain (Bib) and Prip-like (PripL) channels (2) aquaglyceroporins (Glp) and (3) unorthodox aquaporins (Aqp12-like). In Hexapoda, two additional subfamilies exist as Drip and a recently classified entomoglyceroporin (Eglp) group. Cloning and remapping the louse cDNAs to the genomic DNA revealed that they are encoded by 1–7 exons, with two of the Glps being expressed as N-terminal splice variants (Glp1_v1, −1_v2, −3_v1, −3_v2). Heterologous expression of the cRNAs in amphibian oocytes demonstrated that PripL transports water and urea, while Bib does not. Glp1_v1, −2, −3_v1 and −3_v2 each transport water, glycerol and urea, while Glp1_v2 and the Aqp12-like channels were retained intracellularly. Transcript abundance analyses revealed expression of each louse paralog at all developmental stages, except for glp1_v1, which is specific to preadult and adult males.ConclusionsOur data suggest that the aquaporin repertoires of extant arthropods have expanded independently in the different lineages, but can be phylogenetically classified into three major grades as opposed to four present in deuterostome animals. While the aquaporin repertoire of Atlantic salmon represents a 6-fold redundancy compared to the louse, the functional assays reveal that the permeation properties of the different crustacean grades of aquaporin are largely conserved to the vertebrate counterparts.

【 授权许可】

CC BY   
© Stavang et al. 2015