Localization of human (pro)renin receptor lacking the transmembrane domain on budded baculovirus of Autographa californica multiple nucleopolyhedrovirus

(Pro)renin receptor and V-ATPase: from Drosophila to humans

A decade ago, the (P)RR [(pro)renin receptor] was discovered and depicted as a potential activator of the tissue renin-angiotensin system. For this reason, the role of the (P)RR in cardiovascular diseases and diabetes has been particularly studied. However, the discovery of embryonic lethality after (P)RR gene deletion in mouse and zebrafish paved the way for additional roles of (P)RR in cell homoeostasis. Indeed, the (P)RR has been shown to associate with vacuolar H+-ATPase, hence its other name ATP6ap2. Developmental studies in Xenopus and Drosophila have revealed an essential role of this association to promote the canonical and non-canonical Wnt signalling pathways, whereas studies with tissue-specific gene deletion have pointed out a role in autophagy. The present review aims to summarize recent findings on the cellular functions of (P)RR emerging from various mutated and transgenic animal models.

Display of the human (pro)renin receptor on Bombyx mori nucleopolyhedrovirus (BmNPV) particles using Bm cells

The human (pro)renin receptor (hPRR) was displayed on the surface of Bombyx mori nucleopolyhedrovirus (BmNPV) with and without fusion to glycoprotein 64 (GP64) of the BmNPV. hPRR1 is a native hPRR with an additional FLAG peptide sequence inserted between the signal peptide and prorenin-binding domain. hPRR2 has the prorenin-binding domain inserted between amino acid residues (81)Asp and (82)Pro of GP64. hPRR4 has the prorenin-binding domain inserted in (81)Asp and (320)Met of partially deleted GP64. Incorporation of hPRR was confirmed in recombinant BmNPV (rBmNPV) but not in cysteine protease-deleted rBmNPV. hPRR1 was observed in ER, but hPRR2 and hPRR4 were observed around the endoplasmic reticulum (ER) and in its periphery. rBmNPV-hPRR1 and -hPRR2, carrying hPRR1 and hPRR2 respectively, showed binding affinity to human renin, but rBmNPV-hPRR4 did not. The presence of hPRR4 of rBmNPV-hPRR4 was confirmed in western blotting under nonreducing conditions, suggesting that although hPRR4 was incorporated in rBmNPV-hPRR4, it behaved as a non-functional aggregate. This rBmNPV display system can also be used for analyzing a ligand-receptor interaction.