title: Chemical genetic screening identifies critical pathways in anthrax lethal toxin-induced pathogenesis.
abstract: Anthrax lethal toxin (LT)-induced cell death via mitogen-activated protein kinase kinase (MAPKK) cleavage remains questionable. Here, a chemical genetics approach was used to investigate what pathways mediate LT-induced cell death. Several small molecules were found to protect macrophages from anthrax LT cytotoxicity and MAPKK from cleavage by lethal factor (LF), without inhibiting LF enzymatic activity or cellular proteasome activity. Interestingly, the compounds activated MAPK-signaling molecules, induced proinflammatory cytokine production, and inhibited LT-induced macrophage apoptosis in a concentration-dependent manner. We propose that induction of antiapoptotic responses by MAPK-dependent or -independent pathways and activation of host innate responses may protect macrophages from anthrax LT-induced cell death. Altering host responses through a chemical genetics approach can help identify critical cellular pathways involved in the pathogenesis of anthrax and can be exploited to further explore host-pathogen interactions.
authors: Target Structure-Based Drug Discovery Group, SAIC-Frederick, Inc., NCI-Frederick, Frederick, Maryland 21702, USA. rekha.panchal@amedd.army.mil
authors: Rekha G
authors: RG
authors: Panchal
authors: Gordon
authors: G
authors: Ruthel
authors: Katherine C
authors: KC
authors: Brittingham
authors: Douglas
authors: D
authors: Lane
authors: Tara A
authors: TA
authors: Kenny
authors: Rick
authors: R
authors: Gussio
authors: John S
authors: JS
authors: Lazo
authors: Sina
authors: S
authors: Bavari
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D001427:Bacterial Toxins / Q000633:toxicity*; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D016207:Cytokines / Q000378:metabolism; D005820:Genetic Testing / Q000379:methods; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D051379:Mice; D018613:Microscopy, Confocal; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors*; D009336:Necrosis; D020687:cdc25 Phosphatases / Q000037:antagonists & inhibitors
chemical_list: D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D018797:Cell Cycle Proteins; D016207:Cytokines; C030325:anthrax toxin; D020929:Mitogen-Activated Protein Kinase Kinases; D020687:cdc25 Phosphatases