Intracellular cholesterol trafficking is dependent upon NPC2 interaction with Lysobisphosphatidic Acid

Abstract
Data availability
Article and author information
Metrics

Abstract

Unesterified cholesterol accumulation in the late endosomal/lysosomal (LE/LY) compartment is the cellular hallmark of Niemann-Pick C (NPC) disease, caused by defects in the genes encoding NPC1 or NPC2. We previously reported the dramatic stimulation of NPC2 cholesterol transport rates to and from model membranes by the LE/LY phospholipid lysobisphosphatidic acid (LBPA). It had been previously shown that enrichment of NPC1-deficient cells with LBPA results in cholesterol clearance. Here we demonstrate that LBPA enrichment in human NPC2-deficient cells, either directly or via its biosynthetic precursor phosphtidylglycerol (PG), is entirely ineffective, indicating an obligate functional interaction between NPC2 and LBPA in cholesterol trafficking. We further demonstrate that NPC2 interacts directly with LBPA and identify the NPC2 hydrophobic knob domain as the site of interaction. Together these studies reveal a heretofore unknown step of intracellular cholesterol trafficking which is critically dependent upon the interaction of LBPA with functional NPC2 protein.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files

The following previously published data sets were used

(2006) 1nep, Epididymal secretory protein E1
Orientation of Proteins in Membranes (OPM) Database.

https://opm.phar.umich.edu/proteins/271
1. National Library of Medicine (US)
2. National Center for Biotechnology Information
(1988) NPC intracellular cholesterol transporter 2 isoform 2 precursor [Homo sapiens]
NCBI Protein Database, NP_006423.1.

https://www.ncbi.nlm.nih.gov/protein/NP_006423.1
1. National Library of Medicine (US)
2. National Center for Biotechnology Information
(1988) NPC intracellular cholesterol transporter 2 precursor [Mus musculus]
NCBI Protein Database, NP_075898.1.

https://www.ncbi.nlm.nih.gov/protein/NP_075898.1
1. National Library of Medicine (US)
2. National Center for Biotechnology Information
(1988) NPC intracellular cholesterol transporter 2 precursor [Bos taurus]
NCBI Protein Database, NP_776343.1.

https://www.ncbi.nlm.nih.gov/protein/NP_776343.1
1. National Library of Medicine (US)
2. National Center for Biotechnology Information
(1988) epididymal secretory protein E1 [Felis catus]
NCBI Protein Database, XP_003987882.1.

https://www.ncbi.nlm.nih.gov/protein/XP_003987882.1
1. National Library of Medicine (US)
2. National Center for Biotechnology Information
(1988) NPC intracellular cholesterol transporter 2 precursor [Pan troglodytes]
NCBI Protein Database, NP_001009075.1.

https://www.ncbi.nlm.nih.gov/protein/NP_001009075.1
1. National Library of Medicine (US)
2. National Center for Biotechnology Information
(1988) NPC2 [Saccharomyces cerevisiae]
NCBI Protein Database, KZV12184.1.

https://www.ncbi.nlm.nih.gov/protein/KZV12184.1

Article and author information

Author details

Leslie A McCauliff

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Annette Langan

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Ran Li

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Olga Ilnytska

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Debosreeta Bose

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Miriam Waghalter

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Kimberly Lai

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Peter C Kahn

Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, United States

Competing interests
The authors declare that no competing interests exist.
Judith Storch

Department of Nutritional Sciences, Rutgers University, New Brunswick, United States

For correspondence
storch@sebs.rutgers.edu

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0001-5482-1777

Funding

Ara Parseghian Medical Research Foundation

Olga Ilnytska
Judith Storch

American Heart Association (11PRE7330012)

Leslie A McCauliff

American Heart Association (18CDA34110230)

Olga Ilnytska

American Heart Association (14GRNT19990014)

Judith Storch

National Institutes of Health (GM 1125866)

Judith Storch

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.