| First Author | Huang M | Year | 2019 |
| Journal | Metabolism | Volume | 94 |
| Pages | 88-95 | PubMed ID | 30831144 |
| Mgi Jnum | J:291920 | Mgi Id | MGI:6445035 |
| Doi | 10.1016/j.metabol.2019.02.005 | Citation | Huang M, et al. (2019) PAQR3 modulates blood cholesterol level by facilitating interaction between LDLR and PCSK9. Metabolism 94:88-95 |
| abstractText | OBJECTIVE: Low-density lipoprotein cholesterol (LDL-C) is the hallmark of atherosclerotic cardiovascular diseases. The hepatic LDL receptor (LDLR) plays an important role in clearance of circulating LDL-C. PCSK9 facilitates degradation of LDLR in the lysosome and antagonizing PCSK9 has been successfully used in the clinic to reduce blood LDL-C level. Here we identify a new player that modulates LDLR interaction with PCSK9, thus controlling LDLR degradation and cholesterol homeostasis. METHODS: The blood LDL-C and cholesterol levels were analyzed in mice with hepatic deletion of Paqr3 gene. The half-life of LDLR was analyzed in HepG2 cells. The interaction of PAQR3 with LDLR and PCSK9 was analyzed by co-immunoprecipitation and immunofluorescent staining. RESULTS: The blood LDL-C and total cholesterol levels in the mice with hepatic deletion of Paqr3 gene were significantly lower than the control mice after feeding with high-fat diet (p<0.001 and p<0.05 respectively). The steady-state level of LDLR protein is elevated by Paqr3 knockdown/deletion and reduced by PAQR3 overexpression. The half-life of LDLR protein is increased by Paqr3 knockdown and accelerated by PAQR3 overexpression. PAQR3 interacts with the beta-sheet domain of LDLR and the P-domain of PCSK9 respectively. In addition, PAQR3 can be localized in early endosomes and colocalized with LDLR, PCSK9 and LDL. Mechanistically, PAQR3 enhances the interaction between LDLR and PCSK9. CONCLUSION: Our study reveals that PAQR3 plays a pivotal role in controlling hepatic LDLR degradation and blood LDL-C level via modulating LDLR-PCSK9 interaction. |
