Reactome | OSBPs transport 25OH-CHOL from ER membrane to plasma membrane

OSBPs transport 25OH-CHOL from ER membrane to plasma membrane

Stable Identifier

R-HSA-8867667

Type

Reaction [transition]

Species

Homo sapiens

Compartment

cytosol, endoplasmic reticulum membrane, plasma membrane

ReviewStatus

5/5

Locations in the PathwayBrowser

Expand all

General

SBML | | PDF

SVG | | PPTX | SBGN

OSBPs transport 25OH-CHOL from ER membrane to plasma membrane

Click the image above or here to open this reaction in the Pathway Browser
The layout of this reaction may differ from that in the pathway view due to the constraints in pathway layout

Oxysterol-binding proteins (OSBPs) and OSBP-related proteins (ORPs) comprise a 12-member mammalian gene family of intracellular lipid receptors which bind oxygenated cholesterol derivatives and are thought to mediate sterol and phospholipid synthesis (Olkkonen & Li 2013, Weber-Boyvat et al. 2013). A conserved OSBP homology domain (OHD) binds sterols and lipids and a pleckstrin homology (PH) domain and two phenylalanines in an acidic tract (FFAT) motif mediate interaction with organelle membranes (Olkkonen 2015). The primary function of the protein family remains unresolved. Most (OSBPL2,3,6,7,9 and 1A), if not all of the OSBPLs are thought to bind and coordinate distribution of oxygenated cholesterol derivatives such as 25-hydroxycholesterol (25OH-CHOL). Oxysterol-binding protein 2 (OSBP2, aka ORP4) is primarily expressed in brain, and to a lesser extent in heart, skeletal muscle, spleen and kidney. It has a diffuse cytoplasmic localisation profile and is a high-affinity 25OH-CHOL binding protein (Wang et al. 2002, Suchanek et al. 2007). RNAi silencing of all OSBP2 variants in HEK293 and HeLa cells resulted in growth arrest but not cell death, suggesting OSBP2 is essential for cell proliferation and survival (Charman et al. 2014).

Literature References

PubMed ID	Title	Journal	Year
17428193	The mammalian oxysterol-binding protein-related proteins (ORPs) bind 25-hydroxycholesterol in an evolutionarily conserved pocket Hynynen, R, Radzikowska, A, Olkkonen, VM, Johansson, M, Saarinen, H, Suchanek, M, Wohlfahrt, G, Lehto, M, Thiele, C	Biochem. J.	2007
23428468	Oxysterol-binding proteins: functions in cell regulation beyond lipid metabolism Olkkonen, VM, Zhong, W, Weber-Boyvat, M, Yan, D	Biochem. Pharmacol.	2013
23830809	Oxysterol-binding proteins: sterol and phosphoinositide sensors coordinating transport, signaling and metabolism Olkkonen, VM, Li, S	Prog. Lipid Res.	2013
26715851	OSBP-Related Protein Family in Lipid Transport Over Membrane Contact Sites Olkkonen, VM	Lipid Insights	2015
11802775	Oxysterol-binding-protein (OSBP)-related protein 4 binds 25-hydroxycholesterol and interacts with vimentin intermediate filaments Wang, C, JeBailey, L, Ridgway, ND	Biochem. J.	2002
24742681	Oxysterol-binding protein (OSBP)-related protein 4 (ORP4) is essential for cell proliferation and survival Kreplak, L, Colbourne, TR, Charman, M, Pietrangelo, A, Ridgway, ND	J. Biol. Chem.	2014