title: Molecular characterization and transcriptional regulation of the renin-angiotensin system genes in Senegalese sole (Solea senegalensis Kaup, 1858): differential gene regulation by salinity.
abstract: In this work, the complete cDNA sequence encoding angiotensinogen (agt) in the euryhaline flatfish Senegalese sole was obtained. Additionally, putative coding sequences belonging to other renin-angiotensin system (RAS) genes including renin (ren), angiotensin-converting enzyme (ace), angiotensin-converting enzyme 2 (ace2), as well as angiotensin II receptor type I (agtr1) and type II (agtr2), were also identified. In juvenile tissues, agt transcripts were mainly detected in liver, ren in kidney, ace and ace2 in intestine, agtr1 in kidney and brain, and agtr2 in liver and kidney. Expression analysis of the six RAS genes after a salinity shift revealed a clear increase of agt mRNA abundance in liver just after transferring soles to high salinity water (60 ppt) with a peak at 48 h. Moreover, gene expression analysis in gills showed transcriptional regulation of ace and agtr1 at 48 h and agtr2 at 96 h after transferring soles to 60 ppt. Incubation of larvae before mouth opening (until 3 days post hatch; dph) at low salinity (10 ppt) resulted in a coordinated transcriptional up-regulation of RAS genes. Nevertheless, no differences in mRNA abundance between salinities were observed when larvae were cultivated to low salinity after mouth opening. Whole-mount in situ hybridization (WISH) signal for agt and ace in 3 dph larvae incubated at 10 ppt and 35 ppt confirmed that the former gene was mainly expressed in liver whereas the later gene was mainly located in pharynx and posterior gut, without pronounced differences in intensity between salinities. Possible physiological significance of all these results is discussed.
authors: IFAPA Centro El Toruño, 11500 El Puerto de Santa María, Cádiz, Spain.
authors: Paula
authors: P
authors: Armesto
authors: Ifremer, Laboratoire d'Ecotoxicologie, Place Gaby Coll, BP7, 17137 L'Houmeau, France.
authors: Xavier
authors: X
authors: Cousin
authors: IFAPA Centro El Toruño, 11500 El Puerto de Santa María, Cádiz, Spain.
authors: Emilio
authors: E
authors: Salas-Leiton
authors: IFAPA Centro El Toruño, 11500 El Puerto de Santa María, Cádiz, Spain.
authors: Esther
authors: E
authors: Asensio
authors: IFAPA Centro El Toruño, 11500 El Puerto de Santa María, Cádiz, Spain.
authors: Manuel
authors: M
authors: Manchado
authors: Fitoplancton Marino, S.L., Dársena Comercial S/N (Muelle Pesquero), 11500 El Puerto de Santa María, Cádiz, Spain. Electronic address: carlos.infante@easyalgae.com.
authors: Carlos
authors: C
authors: Infante
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005412:Flatfishes / Q000235:genetics*; D005786:Gene Expression Regulation; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics; D012084:Renin-Angiotensin System / Q000235:genetics*; D054712:Salinity; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
chemical_list: D012333:RNA, Messenger
keywords: Angiotensinogen; Gene expression; Osmoregulation; Renin–angiotensin system; Senegalese sole