Role of ORP10 in NPC1L1-dependent cholesterol transport

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K08277
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General medical chemistry
• Research Institution: Tottori University
• Principal Investigator: Ninomiya Haruaki 鳥取大学, 医学部, 教授 (80212124)
• Co-Investigator(Renkei-kenkyūsha): Nakasone Naoe 鳥取大学, 医学部, 助教 (30632947)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: Niemann-Pick C1 Like1 / ORP10 / cholesterol

Outline of Final Research Achievements

In HEK cells stably expressing Niemann-Pick C1 Like 1 (NPC1L1)-YFP, overexpression of oxysterol-binding protein (OSBP)-related protein 10 (ORP10) increased the protein level of NPC1L1-YFP and enhanced cellular cholesterol uptake. The latter effect was more prominent with the ORP10 D254 isoform, which has been shown to predispose to hyper-LDL cholesterolemia, than with the N254 isoform. In reciprocal experiments, Co-immunoprecipitation (IP) assays showed that ORP10 interacted with both NPC1L1 and Numb via its N-terminal pleckstrin homology domain and C-terminal OSBP-related ligand-binding domain, respectively。Fluorescence resonance energy transfer (FRET) analyses revealed a clear difference in the intramolecular FRET efficacy between the two isoforms. These findings suggested that ORP10 regulates NPC1L1 internalization and that differential impact on NPC1L1-dependent cholesterol transport may underlie association of the D254 isoform with hyper-LDL cholesterolemia.

Free Research Field

生化学