5z65
Crystal structure of porcine aminopeptidase N ectodomain in functional form
Structural highlights
FunctionAMPN_PIG Broad specificity aminopeptidase. Plays a role in the final digestion of peptides generated from hydrolysis of proteins by gastric and pancreatic proteases. May be involved in the metabolism of regulatory peptides of diverse cell types, responsible for the processing of peptide hormones, such as angiotensin III and IV, neuropeptides, and chemokines and involved the cleavage of peptides bound to major histocompatibility complex class II molecules of antigen presenting cells. May have a role in angiogenesis (By similarity). It is able to degrade Leu-enkephalin and Met-enkephalin but not cholecystokinin CCK8, neuromedin C (GRP-10), somatostatin-14, substance P and vasoactive intestinal peptide. In case of porcine transmissible gastroenteritis coronavirus (TGEV) and porcine respiratory coronavirus (PRCoV) infections, serves as a receptor for TGEV and PRCoV spike glycoprotein in a species-specific manner.[1] [2] [3] [4] [5] Publication Abstract from PubMedPorcine epidemic diarrhea (PED) has caused huge economic losses to the global pork industry. Infection by its causative agent PED virus (PEDV), an Alpha-coronavirus, was previously proven to be mediated by its spike (S) glycoprotein and a cellular receptor porcine aminopeptidase N (pAPN). Interestingly, some recent studies have indicated that pAPN is not a functional receptor for PEDV. To date, there is a lack of a direct evidence for the interaction between pAPN and PEDV S protein in vitro. Here, we prepared pAPN ectodomain and the truncated variants of PEDV S protein in Drosophila S2 cells. These recombinant proteins were homogeneous after purification by metal-affinity and size-exclusion chromatography. We then assayed the purified target proteins through immunogenicity tests, PEDV binding interference assays, circular dichroism (CD) measurements, pAPN activity assay and structural determination, demonstrating that they were biologically functional. Finally, we characterized their interactions by gel filtration chromatography, native-polyacrylamide gel electrophoresis (PAGE) and surface plasmon resonance (SPR) analyses. The results showed that their affinities were too low to form complexes, which suggest that pAPN may be controversial as the genuine receptor for PEDV. Therefore, further research needs to be carried out to elucidate the interaction between PEDV and its genuine receptor. Characterization of the interaction between recombinant porcine aminopeptidase N and spike glycoprotein of porcine epidemic diarrhea virus.,Sun YG, Li R, Jiang L, Qiao S, Zhi Y, Chen XX, Xie S, Wu J, Li X, Deng R, Zhang G Int J Biol Macromol. 2018 Oct 1;117:704-712. doi: 10.1016/j.ijbiomac.2018.05.167., Epub 2018 May 24. PMID:29802920[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
