Genomic characterization and expression analysis of the first nonmammalian renin genes from zebrafish and pufferfish

Abstract

Renin is a key enzyme in the renin-angiotensin system (RAS), a pathway which plays an important physiological role in blood pressure and electrolyte homeostasis. The origin of the RAS is believed to have accompanied early evolution of vertebrates. However, renin genes have so far only been unequivocally identified in mammals. Whether or not a bona fide renin gene exists in nonmammalian vertebrates has been an intriguing question of physiological and evolutionary interest. Using a genomic analytical approach, we identified renin genes in two nonmammalian vertebrates, zebrafish (Danio rerio) and pufferfish (Takifugu rubripes). Phylogenetic analysis demonstrates that the predicted fish renins cluster together with mammalian renins to form a distinct subclass of vertebrate aspartyl proteases. RT-PCR results confirm generation of the predicted zebrafish mRNA and its expression in association with the opisthonephric kidney of adult zebrafish. Comparative in situ hybridization analysis of wild-type and developmental mutants indicates that renin expression is first detected bilaterally in cells of the interrenal primordia at 24 h postfertilization, which subsequently migrate to lie adjacent to, but distinct from, the glomerulus of the developing pronephric kidney. Our report provides the first molecular evidence for the existence of renin genes in lower vertebrates. The observation that the earliest renin-expressing cells, arising during ontogeny of this teleost vertebrate, are of adrenocortical lineage raises an interesting hypothesis as regards the origin of renin-expressing cells in the metanephric kidney of higher vertebrates.

Renin expression in developing zebrafish is associated with angiogenesis and requires the Notch pathway and endothelium

“…A 6.46-kb region from the ren translational initiation site (43) to the neighboring upstream zgc: 162200 gene was isolated from BAC CH73-270F23 (CHORI, Oakland, CA) using the following primer sequences with attB sites for gateway recombination into pDONR4-PIR (Invitrogen): ren forward 5=-GGGGACAACTTTGTATAGAAAAGTTGCTCGCCACACG-GTTGTGAAA-3= and ren reverse 3=-GGGGACTGCTTTTTTGTA-CAAACTTGCTCTCACTGATGGATCTAT-5=. The fragment was recombined upstream of red fluorescent protein (RFP) and simian virus 40 polyA by three-way gateway cloning into pDestTol2CG2 (containing minimal tol2 ends and cardiac myosin light chain:GFP) of the tol2 system (38).…”

“…The piscine renin gene (ren) was characterized in zebrafish and fugu by Liang et al (43). Teleosts represent the taxon with the most primitive renin and RAS known (14).…”

Expression of endocrine genes in zebrafish larvae in response to environmental salinity

“…Renin, an enzyme that converts angiotensinogen to angiotensin I, is secreted from the juxtaglomerular cells of the kidney in response to a decrease in blood pressure (Gomez et al 1988, Jones et al 1990. In zebrafish, expression of renin has been shown in the juxtaglomerular cells, although no physiological function has been analyzed yet (Liang et al 2004).…”

Signal transduction of the (pro)renin receptor as a novel therapeutic target for preventing end-organ damage

“…80 Consistently, the ligand renin is only expressed in mammalian and-as recently demonstrated in zebrafish-nonmammalian vertebrates. 81 Angiotensinogen, the substrate of renin, is also expressed in zebrafish. 82 It was shown by different groups that full-length (P)RR is mainly localized intracellularly in perinuclear compartments, most likely corresponding to the endoplasmic reticulum.…”