Human cGAS inhibitor

Specific inhibitor of human cGAS

Inhibition of human cGAS signaling by G140

G140 is a small-molecule inhibitor of the double-stranded DNA (dsDNA) sensor, cGAS (cyclic GMP-AMP synthase; cGAMP synthase). G140 was identified in an in vitro high-throughput screen targeted towards recombinant human cGAS (hcGAS). Notably, G140,  a pyrido-[4,3-b]-indole, features a methyl pyrazole group that significantly improves its potency and inhibitory activity against hcGAS [1].

cGAS is the primary sensor of cytosolic dsDNA, a danger signal indicating possible disturbances in homeostasis caused by infection, sterile tissue damage, and/or cancer. cGAS signals through STING and TBK1 to activate both the type I IFN and NF‑κB pathways [2,3].  

Unlike RU.521, a previously developed murine cGAS inhibitor, G140 has been shown to specifically inhibit the activation of the hcGAS-induced type I IFN pathway [1].  G140 has been shown to have a dose-dependent inhibitory activity in both monocytes (i.e. THP1 cells) and primary human macrophages, with no off-target effects on a variety of different sensors [1]. Furthermore, G140 has been shown to exhibit inhibitory activity on cGAS-mediated activation of NF‑κB [1].

Key features of G140:

• G140 specifically inhibits human cGAS in a dose-dependent manner.
• G140 inhibits both cGAS-mediated IRF and NF-κB signaling.
• Each lot of G140 is highly pure (>95%) and functionally tested.

Please note: InvivoGen also offers the specific murine cGAS inhibitor RU.521

References:

1. Lama, L. et al. 2019. Development of human cGAS-specific small-molecule inhibitors for repression of dsDNA-triggered interferon expression. Nat Commun 10, 2261.
2. Gao, D. et al. 2015. Activation of cyclic GMP-AMP synthase by self-DNA causes autoimmune diseases. PNAS 112, E5699-5705.
3. Abe, T. et al. 2014. Cytosolic-DNA-mediated, STINGdependent proinflammatory gene induction necessitates canonical NF-kappaB activation through TBK1. J Virol 88, 5328-5341.
 

Figures

G140 inhibits human cGAS in a dose-dependent response. THP1-Dual™ cells were incubated with increasing concentrations (0 - 25 μM) of G140 for 3 hours. Following this, G3-YSD (1 μg/ml), a specific cGAS agonist, was complexed with LyoVec™ and transfected into the cells. After overnight incubation, activation of cGAS was assessed by measuring IRF-dependent Lucia activity using QUANTI‑Luc™, a detection reagent. Data are shown as percentage (%) of cGAS activity ± std error.

G140 inhibits human cGAS in a dose-dependent response. THP1-Dual™ cells were incubated with increasing concentrations (0 - 25μM) of G140 for 3 hours. Following this, G3-YSD (1 μg/ml), a specific cGAS agonist, was complexed with LyoVec™ and transfected into the cells. After overnight incubation, activation of cGAS was assessed by measuring NF‑κB -dependent SEAP activity using QUANTI-Blue™ Solution, a detection reagent. Data are shown as percentage (%) of cGAS activity ± std error.

Specific inhibition of human cGAS by G140. THP1-Dual™ cells were incubated in the presence or absence of 6 μM G140 for 3 hours. Following this, G3-YSD (1 μg/ml), a specific cGAS agonist, or 3p-hpRNA (1 μg/ml), a specific RLR agonist were complexed with LyoVec™ and transfected into the cells. After overnight incubation, the IRF response was assessed using QUANTI‑Luc™, a detection reagent. Data are shown as a percentage (%) of IRF-induced Lucia luciferase activity.

Specific inhibition of human cGAS by G140. THP1‑Dual™ cells (WT) and THP-Dual™ KO-cGAS (KO-cGAS) cells were incubated in the presence or absence of 6 μM G140 for 3 hours. Following this, 2’3’-cGAMP (10 μg/ml), a STING agonist was added to the cells. After overnight incubation, the IRF response was assessed using QUANTI‑Luc™. Data are shown as a percentage (%) of STING-induced Lucia luciferase activity.

Specifications

Formula: C₁₇H₁₆Cl₂N₄O₂

Molecular weight: 379.24 g/mol

Solubility: 5 mg/ml (13.18 mM) in DMSO

Working concentration: 1 - 20 µM for cell culture assays.

Quality control:

• Purity ≥ 95% (UHPLC).
• Inhibition of cGAS has been confirmed using cellular assays
• The absence of bacterial contamination (e.g. lipoproteins and endotoxins) has been confirmed using HEK-Blue™ TLR2 and HEK‑Blue™ TLR4 cells.

Contents

• 2 mg G140 (provided as a dried powder)

G140 is shipped at room temperature.

Store at -20°C.

Resuspended product is stable for at least 6 months when properly stored.

Avoid repeated freeze-thaw cycles.

Details

Chemical structure of G140