Table 1. Proteins/Factors involved in regulating RCT model.

Protein Name	Abbr	Isoforms	Function/regulation target	Reference
Main proteins
Caveolins	Cav	Cav-1, Cav-2, Cav-3	Transporter of intracellular cholesterol	7
ATP-binding cassette transporter	ABC	ABCA1, ABCG1, ABCG5, ABCG8	Transmembrane transporter of cholesterol	26, 111, 112, 113, 114
Scavenger receptor	SR	SR-A1, SR-A2, SR-B1, CD36, LOX-1	Transmembrane transporter of cholesterol; LDL/HDL receptor	54, 115, 116, 117
Apolipoprotein	Apo	Apo-AI, Apo-AII Apo-AIV, Apo-B, Apo-CI, CII, CIII, CIV, Apo-E	Apo-A1 is a main transporter of cholesterol in HDL Apo-E in HDL accepts cholesterol from macrophases, and makes LCAT activation Apo-C regulates the activations of LCAT, CETP and LPL	37, 118, 119, 120
Regulation system
Nuclear factors
Sterol regulatory element binding protein	SREBP	SREBP-1a, SREBP-1c, SREBP-2	Regulate the expressions of Cav-1, LDL-R, ABCA1, SB-B1, HMG-CoA reducase, fatty acid synthase	43, 44, 94, 121, 122, 123
Liver X receptor	LXR	LXRα, LXRβ	Regulate the expressions of ABCA1, ABCG1, ABCG4, ABCG5, ABCG8, SR-B1, SREBP	114, 124, 125, 126
Peroxisome proliferator-activated receptor	PPAR	PPARα, PPARβ, PPARδ, PPAR γ1, PPAR γ2, PPAR γ3	Regulate the expressions of Cav-1, ABCA1, ABCG1, SR-B1, apoE, apoA1, apoA2	52, 53, 55, 95, 127
Lipid transportation protein
Sterol carrier protein	SCP	SCP-2, SCP-x	Transfer steroids and probably also phospholipids and ganglio- sides between cellular membranes	128, 129
Phospholipid transfer protein	PLTP		Phospholipid exchange between lipoproteins, contribute to transform from CM, VLDL, LDL to HDL, from HDL3 to HDL2, pre-β-HDL	130, 131, 132, 133
Cholesteryl ester transfer protein	CETP		Lipid exchange between HDL and other lipoprotein, plasma membrane	134, 135
Niemann-Pick disease type C	NPC	NPC-1, NPC-2	Lipid, especially free cholesterol flows through endosome, lysosome, Golgi complex, ER, plasma membrane	136
Cholesterol synthesis enzyme
Acyl-CoA:Cholesterol acyltrans- ferase	ACAT	ACAT1 ACAT2	Catalyze free cholesterol and long chain acyl-CoA to form cholesterol ester	137
Lecithin:Cholesterol acyltrans- ferase	LCAT	Mature HDL and Esterize cholesterol		138
Lipase		Lipopotein lipase Endothelial lipase Hepatic lipase	Hydrolyze endogeous TG and transfers cholesterol, phos- pholipid and apolipoprotein among lipoproteins.	139
Cholesterol-metabolizing cytochrome P450	CYP	CYP27A1 CYP7A1 CYP46A1	Oxidate cholesterol and maintain cholesterol homeostasis	140, 141
Other regulation factors
Cyclophilin	Cyp	Cyp A, Cyp B, Cyp D, Cyp 40	Cyclophilins catalyze the isomerization of peptide bonds from trans form to cis form at proline residues and facilitates protein folding	85, 86
Adipophilin	ADRP		ADRP is involved in the movement of cholesterol inside of cytosol	142
Lipid		Phospholipid, Sterol, Oxy-sterol, Retinoid, Cholesterol	Lipid regulates intracellular lipid homeostasis and the movement of cholesterol between cellular membranes	48, 92, 143, 144
Cyclic adenosine monophosphate	cAMP		cAMP activates APK to activate lipase catalyzing triglyceride into free fatty acid and glycerol	145
Steroidogenic acute regulatory protein	StAR		StAR transforms cholesterol in mitochondria to steroid	146
Annexin-2	ANX2		ANX2 mediates cholesterol transportation	96