Table 2.

GPCR-interacting proteins that regulate receptor anterograde transport^*

Interacting proteins	GPCRs	Surface receptor	Binding domains	References
Group I: Proteins interacting with the C-termini of GPCRs
Homer1a	mGluR1a	↑/No effect	PPXXFR	[123,124,128]
	mGluR5	No effect	PPXXFR	[123, 128]
Homer1b	mGluR5	↓	ND	[125,126]
	mGluR1a	↓	ND	[125]
Homer1c	mGluR1a	↑/No effect	PPXXFR	[123,127,128]
	mGluR5	↓	ND	[128]
GEC1	KOR	↑	C-terminal 35 residues	[132]
DRiP78	D1R	Dual roles	FXXXFXXXF	[37]
	M2-MR	↓	ND	[37]
	AT1R	↑	YXFXXXXFXXY	[133]
ATIP/ATBP50	AT2R	↑	CT	[134,135]
Usp4	A2AR	↑	C-terminal 52 residues	[136]
gC1q-R	α1B-AR	↓	Arginine-rich region	[137]
Skb1Hs	SSTR1	↑	CT and NPXXY motif	[138]
Tctex-1	Rhodopsin	↑	CT	[139]
Protein 4.1G	mGluR1a	↑	CT	[143]
	PTHR	↑	N-terminal 24 residues	[144]
Group II: Proteins interacting with the third intracellular loops of GPCRs
Neurofilament-M	D1R	↓	i3 loop	[142]
Protein 4.1G	A1AR	↓	i3 loop	[145]
Protein 4.1N	D2R	↑	N-portion of i3 loop	[146]
	D3R	↑	N-portion of i3 loop	[146]
Filamin A	D2R	↑	N-portion of i3 loop	[147,148]
Protachykinin	DOR	↑	i3 loop	[153]
Group III: Other GPCR interacting proteins
RAMP1, 2, 3	CRLR	↑	N-terminus	[154,155]
RAMP 1, 3	CaSR	↑	ND	[162]
NinaA	Rhodopsin	↑	ND	[163,164]
RanBP2	Opsin	↑	ND	[165]
ODR-4	ODR-10	↑	ND	[166]
	U131	↑	ND	[167]
HSJ1b	Rhodopsin	↓	ND	[168]
M10	V2R pheromone	↑	ND	[169]

^*↑, increase; ↓, decrease; ND, not determined; CT, C-terminus; i3, the third intracellular loop