Rho family proteins (20 human members) comprise a major branch of the Ras superfamily of small GTPases. Like Ras, Rho GTPases function as GDP/GTP-regulated binary on-off switches. Rho GTPases are regulators of a diverse variety of cellular processes that include regulation of cell proliferation, actin cytoskeleton reorganization, and gene expression. EHT 1864, a small molecule inhibitor, which attenuates Rac1 activation by retaining the G-protein in an inert/inactive state, thereby preventing activation of its downstream effector proteins. EHT 1864 possesses high affinity binding to Rac1, as well as the related Rac1b, Rac2, and Rac3 isoforms with KD of 40 nM, 50 nM, 60 nM and 250 nM, respectively. EHT 1864 can inhibit a variety of downstream signaling activities activated by ectopic expression of constitutively-activated Rac1(G12V) and decreased Rac1 association with the isolated Rho GTPase binding domain (RBD) of the p21-activated serine/threonine kinase effector PAK1in vivo. NIH 3T3 cells were incubated for 16 h in serum-free growth medium, either alone, or supplemented with 5 μM EHT 1864 for the last 4 h. It was found that EHT 1864-treated cells showed an ∼80% reduction in PDGF stimulation of lamellipodia which demonstrated that EHT 1864 is a potent and specific inhibitor of PDGF-induced lamellipodia formation[3]. In vitro study, after pre-incubation at varying concentrations of EHT 1864 (0–10 μM) for 1 h, INS-1 832/13 cells were further incubated in the presence of low (2.5 mM) or varying concentrations of glucose (2.5-20 mM) or KCl (40 mM) for 30 min at 37 °C, the result showed that EHT 1864 inhibited glucose-induced Rac1 activation in INS-1 832/13 cells, which resulted in inhibition of GSIS (Glucose-stimulated insulin secretion)[4]. C57BL/6 mice were injected EHT-1864 once a day for 7 days. It was determined that EHT-1864 efficiently inhibits the expression of Rac1, Rac2, and Rac3. And colon length was observed recovered after EHT-1864 treatment for 5 days. Furthermore, less inflammation-associated rectal bleeding and soft stool were observed in the EHT-1864 treatment group, which demonstrate the preventive role of EHT-1864 on acute colitis in mice[5].
作用机制
EHT 1864 binds to Rac1 with high affinity, and retains Rac1 in an inert and inactive state by displacement of pre-bound guanine nucleotide (GDP/GTP).
EHT 1864 细胞研究
细胞系
浓度
检测类型
检测时间
活动说明
数据源
293T cells
Function assay
Effect on Rac1 binding to RhoGDI2 expressed in 293T cells by Western blot analysis
17932039
mouse NIH3T3 cells
Function assay
Effect on Rac1 binding to RhoGDI2 in mouse NIH3T3 cells by Western blot analysis
17932039
mouse NIH3T3 cells
Function assay
Effect on Rac1 binding to RhoGDI1 in mouse NIH3T3 cells by Western blot analysis
搜索
