Heterotrimeric G-protein GTPases

Heterotrimeric G proteins are membrane bound GTPases that are linked to 7-TM receptors. Each G protein contains an α-, β- and γ-subunit and is bound to GDP in the 'off' state. Ligand binding causes a receptor conformational change, detaching the G protein and switching it 'on'.

Gene Data

Heterotrimeric G-protein GTPase Inhibitors

Cat. No. Product Name / Activity
5642 CMPD101
Potent and selective GRK2/3 inhibitor
5245 Ebselen
Selectively inhibits Gq protein signaling
3090 Gallein
Inhibitor of Gβ/γ signaling
3594 GRK2i
GRK2 inhibitory polypeptide; Gβ/γ antagonist
1240 NF 023
Inhibitor of Go/i α-subunits; also P2X1 purinoceptor antagonist
1400 SCH 202676 hydrobromide
Inhibitor of ligand binding to G-protein-coupled receptors
7352 YM 254890
Gα-protein inhibitor; potent inhibitor of Gq/11 signaling


Cat. No. Product Name / Activity
1089 8-Bromo-cGMP, sodium salt
cGMP analog; activates PKG
1193 Melittin
Inhibits Gs and stimulates Gi activity
3097 Pertussis Toxin
Catalyzes ADP-ribosylation of Gi, Go and Gt
1472 Suramin hexasodium salt
Uncouples G proteins from receptors. Also purinoceptor antagonist

Heterotrimeric G proteins are membrane bound GTPases that are linked to 7-TM receptors. Each G protein contains an α-, β- and γ-subunit and is bound to GDP in the 'off' state. Ligand binding to a 7-TM receptor causes a conformational change in the receptor, which detaches the G protein. This switches the G protein to an 'on' state, allowing GTP to displace GDP, thus Gα can activate second messenger signaling cascades.

There are several types of Gα proteins; Gαs and Gαi bind directly to adenylyl cyclase and stimulate or inhibit its activity, leading to an increase or decrease in cAMP levels respectively. Gαq/11 stimulates PLCβ which catalyzes the hydrolysis of PIP2 to the second messengers IP3 and DAG. Gα12/13 are involved in Rho family GTPase signaling. In addition, some Gβγ subunits have active functions; Gβγ coupled to H1 receptors can activate PLA2 and Gβγ coupled to M1 receptors can activate KIR channels.

Rapid termination of the cellular response is required once the concentration of the stimulating ligand decreases. GTP bound to Gα is hydrolyzed rapidly to GDP, Gα is converted to its inactive form and re-associates with the β- and γ-subunits returning to the 'off' state.

External sources of pharmacological information for Heterotrimeric G-protein GTPases :

    Heterotrimeric G Protein Gene Data

    Gene Species Gene Symbol Gene Accession No. Protein Accession No.
    Gαi1 Human GNAI1 NM_002069 P63096
    Mouse Gnai1 NM_010305 NP_034435
    Rat Gnai1 NM_013145 P10824
    Gαi2 Human GNAI2 NM_002070 P04899
    Mouse Gnai2 NM_008138 P08752
    Rat Gnai2 NM_031035 Q5EEY4
    Gαi3 Human GNAI3 NM_006496 P08754
    Mouse Gnai3 NM_010306 Q9DC51
    Rat Gnai3 NM_013106 P08753
    Gαz Human GNAZ NM_002073 P19086
    Mouse Gnaz NM_010311 O70443
    Rat Gnaz NM_013189 P19627
    Gαo1/2 Human GNAO1 NM_020988 P09471
    Mouse Gnao1 NM_001113384 P18872
    Rat Gnao1 NM_017327 Q8R4R5
    Gαt1 Human GNAT1 NM_000172 P11488
    Mouse Gnat1 NM_008140 P20612
    Rat Gnat1 NM_001108780 XP_343481
    Gαt2 Human GNAT2 NM_005272 P19087
    Mouse Gnat2 NM_008141 P50149
    Rat Gnat2 NM_001108950 XP_345272
    Gαt3 Human GNAT3 XM_294370 A8MTJ3
    Mouse Gnat3 NM_001081143 Q3V3I2
    Rat Gnat3 NM_173139 P29348
    Gαs Human GNAS NM_000516 Q8TBC0
    Mouse Gnas NM_010309 Q6R0H7
    Rat Gnas NM_021845 Q9Z213
    Gαolf Human GNAL NM_182978 P38405
    Mouse Gnal NM_177137 Q8CGK7
    Gαq Human GNAQ NM_002072 P50148
    Mouse Gnaq NM_008139 P21279
    Rat Gnaq NM_031036 P82471
    Gα11 Human GNA11 NM_002067 P29992
    Mouse Gna11 NM_010301 P21278
    Rat Gna11 NM_031033 Q63229
    Gα14 Human GNA14 NM_004297 O95837
    Mouse Gna14 NM_008137 P30677
    Rat Gna14 NM_001013151 Q5EAP4
    Gα15 Human GNA15 NM_002068 P30679
    Mouse Gna15 NM_010304 P30678
    Rat Gna15 NM_053542 O88302
    Gα12 Human GNA12 NM_007353 Q03113
    Mouse Gna12 NM_010302 P27600
    Rat Gna12 NM_031034 Q45QM2
    Gα13 Human GNA13 NM_006572 Q14344
    Mouse Gna13 NM_010303 P27601
    Rat Gna13 NM_001013119 Q6Q7Y5
    Gβ1 Human GNB1 NM_002074 P62873
    Mouse Gnb1 NM_008142 P62874
    Rat Gnb1 NM_030987 P54311
    Gβ2 Human GNB2 NM_005273 P62879
    Mouse Gnb2 NM_010312 P62880
    Rat Gnb2 NM_031037 Q9QX35
    Gβ3 Human GNB3 NM_002075 P16520
    Mouse Gnb3 NM_013530 Q61011
    Rat Gnb3 NM_021858 Q45QL4
    Gβ4 Human GNB4 NM_021629 Q9HAV0
    Mouse Gnb4 NM_013531 P29387
    Rat Gnb4 NM_001013910 Q45QL2
    Gβ5 Human GNB5 NM_006578 O14775
    Mouse Gnb5 NM_138719 P62881
    Rat Gnb5 NM_031770 P62882
    Gγt1 Human GNGT1 NM_021955 P63211
    Mouse Gngt1 NM_010314 Q61012
    Rat Gngt1 NM_001135777 XP_001054660
    Gγt2 Human GNGT2 NM_031498 O14610
    Mouse Gngt2 NM_001038664 Q61017
    Rat Gngt2 NM_001135767 XP_001075781
    Gγ2 Human GNG2 NM_053064 P59768
    Mouse Gng2 NM_010315 P63213
    Rat Gng2 AF022087 Q45QK6
    Gγ3 Human GNG3 NM_012202 P63215
    Mouse Gng3 NM_010316 P63216
    Rat Gng3 XM_001074064 O35356
    Gγ4 Human GNG4 NM_004485 P50150
    Mouse Gng4 NM_010317 P50153
    Rat Gng4 XM_001053747 O35357
    Gγ5 Human GNG5 NM_005274 P63218
    Mouse Gng5 NM_010318 Q80SZ7
    Rat Gng5 NM_024377 P63219
    Gγ7 Human GNG7 NM_052847 O60262
    Mouse Gng7 NM_001038655 Q61016
    Rat Gng7 NM_024138 P43425
    Gγ8 Human GNG8 NM_033258 Q9UK08
    Mouse Gng8 NM_010320 P63078
    Rat Gng8 NM_139185 P63077
    Gγ10 Human GNG10 NM_001017998 P50151
    Mouse Gng10 NM_025277 Q9CXP8
    Rat Gng10 NM_053660 Q3KRE3
    Gγ11 Human GNG11 NM_004126 P61952
    Mouse Gng11 NM_025331 P61953
    Rat Gng11 NM_022396 P61954
    Gγ12 Human GNG12 NM_018841 Q9UBI6
    Mouse Gng12 NM_025278 Q9DAS9
    Rat Gng12 XM_578287 O35359
    Gγ13 Human GNG13 NM_016541 Q9P2W3
    Mouse Gng13 NM_022422 Q9JMF3
    Rat Gng13 NM_001135918 Q45QJ8