ABSTRACT
There are currently no approved drugs for the treatment of emerging viral infections, such as dengue and Ebola. Adaptor-associated kinase 1 (AAK1) is a cellular serine-threonine protein kinase that functions as a key regulator of the clathrin-associated host adaptor proteins and regulates the intracellular trafficking of multiple unrelated RNA viruses. Moreover, AAK1 is overexpressed specifically in dengue virus-infected but not bystander cells. Because AAK1 is a promising antiviral drug target, we have embarked on an optimization campaign of a previously identified 7-azaindole analogue, yielding novel pyrrolo[2,3- b]pyridines with high AAK1 affinity. The optimized compounds demonstrate improved activity against dengue virus both in vitro and in human primary dendritic cells and the unrelated Ebola virus. These findings demonstrate that targeting cellular AAK1 may represent a promising broad-spectrum antiviral strategy.
Subject(s)
Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacology , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Pyridines/chemical synthesis , Pyridines/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Cell Line , Chemistry Techniques, Synthetic , Humans , Molecular Docking Simulation , Protein Conformation , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Protein Serine-Threonine Kinases/chemistry , Protein Serine-Threonine Kinases/metabolism , Pyridines/chemistry , Pyridines/metabolism , Structure-Activity RelationshipABSTRACT
The requirement for next-generation antimalarials to be both curative and transmission-blocking necessitates the identification of previously undiscovered druggable molecular pathways. We identified a selective inhibitor of the Plasmodium falciparum protein kinase PfCLK3, which we used in combination with chemogenetics to validate PfCLK3 as a drug target acting at multiple parasite life stages. Consistent with a role for PfCLK3 in RNA splicing, inhibition resulted in the down-regulation of more than 400 essential parasite genes. Inhibition of PfCLK3 mediated rapid killing of asexual liver- and blood-stage P. falciparum and blockade of gametocyte development, thereby preventing transmission, and also showed parasiticidal activity against P. berghei and P. knowlesi Hence, our data establish PfCLK3 as a target for drugs, with the potential to offer a cure-to be prophylactic and transmission blocking in malaria.
Subject(s)
Antimalarials/pharmacology , Molecular Targeted Therapy , Plasmodium falciparum/drug effects , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/antagonists & inhibitors , Protozoan Proteins/antagonists & inhibitors , Animals , Antimalarials/chemistry , Antimalarials/isolation & purification , Antimalarials/therapeutic use , Gametogenesis/drug effects , High-Throughput Screening Assays , Mice , Mice, Inbred BALB C , Plasmodium falciparum/enzymology , Plasmodium falciparum/genetics , Protein Kinase Inhibitors/isolation & purification , Protein Kinase Inhibitors/therapeutic use , Protein Serine-Threonine Kinases/genetics , Protein-Tyrosine Kinases/genetics , Protozoan Proteins/genetics , RNA Splicing/genetics , Small Molecule Libraries/pharmacologyABSTRACT
Potent, selective and broadly characterized small molecule modulators of protein function (chemical probes) are powerful research reagents. The pharmaceutical industry has generated many high-quality chemical probes and several of these have been made available to academia. However, probe-associated data and control compounds, such as inactive structurally related molecules and their associated data, are generally not accessible. The lack of data and guidance makes it difficult for researchers to decide which chemical tools to choose. Several pharmaceutical companies (AbbVie, Bayer, Boehringer Ingelheim, Janssen, MSD, Pfizer, and Takeda) have therefore entered into a pre-competitive collaboration to make available a large number of innovative high-quality probes, including all probe-associated data, control compounds and recommendations on use (
Subject(s)
Molecular Probes/metabolism , Pharmacology/methods , Proteins/metabolism , Technology, Pharmaceutical/methodsABSTRACT
The highly diverse Numb-associated kinase (NAK) family has been linked to broad cellular functions including receptor-mediated endocytosis, Notch pathway modulation, osteoblast differentiation, and dendrite morphogenesis. Consequently, NAK kinases play a key role in a diverse range of diseases from Parkinson's and prostate cancer to HIV. Due to the plasticity of this kinase family, NAK kinases are often inhibited by approved or investigational drugs and have been associated with side effects, but they are also potential drug targets. The presence of cysteine residues in some NAK family members provides the possibility for selective targeting via covalent inhibition. Here we report the first high-resolution structures of kinases AAK1 and BIKE in complex with two drug candidates. The presented data allow a comprehensive structural characterization of the NAK kinase family and provide the basis for rational design of selective NAK inhibitors.