Document text
Principal Investigator: Jan E Carette
Organization: STANFORD UNIVERSITY
Fiscal Year: 2024
Award: $532,301
Funding agency: National Institute of Allergy and Infectious Diseases
PROJECT SUMMARY
Pathogens have evolved to co-opt cellular functions to support their replication and spread while inactivating
innate immune mechanisms that restrict their growth. Discovery and characterization of cellular components that
regulate pathogenesis hold promise for revealing new approaches to treat infectious diseases. Enteroviruses
(EVs) comprise a large genus of single-stranded RNA viruses of positive polarity whose members cause a
number of important human diseases such as poliomyelitis, myocarditis, acute flaccid paralysis and the common
cold. How EVs co-opt cellular functions to promote replication and cause pathogenesis is incompletely
understood. Through robust, unbiased knockout screening approaches, we have discovered that the protein
methyltransferase SETD3 is required for infection by a broad range of human EVs. We showed that enterovirus
replication is severely hampered in human cells lacking SETD3 and that the block occurs during the RNA
replication step. SETD3 is a methyltransferase that mono-methylates actin, thereby regulating actin function.
However, we found that methyltransferase activity of SETD3 is not required for its role in viral replication
indicating that enteroviruses’ reliance on SETD3 is independent of actin methylation. We further showed that
SETD3 interacts with the viral nonstructural 2A protein of several enteroviruses. SETD3 is critically important for
in vivo pathogenesis as we show that Setd3-/- mice are completely protected from lethal intracranial inoculation
with EV-A71 in a neonate model. These findings demonstrate that SETD3 controls pathogenesis for a large class
of viruses with a strong impact on human health including non-polio EVs that can cause severe neurological
symptoms (EV-A71, EV-D68). In this application, we will determine the specific role of SETD3 in viral RNA
replication, structurally characterize the interaction between SETD3 and 2A, and test the hypothesis that
SETD3’s interactions with viral nonstructural proteins are a novel molecular mechanism by which EVs hijack
cellular machinery to enable genome amplification. Furthermore, to study the in vivo role of SETD3 in a mouse
model that recapitulates more faithfully the transmission cycle and pathogenesis of enteric enteroviruses, we will
develop and apply an oral infection model of EV-A71 in immune-competent mice. Our results will provide details
on the molecular mechanisms by which host factors promote enteroviral RNA replication, reveal how non-
catalytic functions of methyltransferases act in microbial pathogenesis and uncover the in vivo role of SETD3 in
promoting EV-A71 replication in diverse cell types involved in initial replication, systemic spread and ultimately
in neuropathogenesis.
Terms: <0-11 years old><Actins><Acute><Acute Nasopharyngitis><Acute Poliomyelitis><Address><Biology><Body Tissues><Cell Body><Cell Function><Cell Physiology><Cell Process><Cells><Cellular Function><Cellular Physiology><Cellular Process><Child><Child Youth><Children (0-21)><Common Cold><Communicable Diseases><Complex><Coxsackie Viruses><Coxsackievirus><Cryo-electron Microscopy><Cryoelectron Microscopy><Crystallographies><Crystallography><Data><EC 2.1.1><EV-68><EV-71><EV-A71><EV-D68><Electron Cryomicroscopy><Enteral><Enteric><Enterovirus><Enterovirus 68><Enterovirus 71><Enterovirus A71><Enterovirus D68><Enterovirus Infections><Family Picornaviridae><Generalized Growth><Genes><Genetic Alteration><Genetic Change><Genetic defect><Genome><Goals><Growth><Health><Host Factor><Host Factor Protein><Human><Human poliovirus><Immunity><Immunocompetent><In Vitro><Infection><Infectious Disease Pathway><Infectious Diseases><Infectious Disorder><Injections><Integration Host Factors><Invaded><Knock-out><Knockout><Knowledge><Medical><Methods><Methylation><Methyltransferase><Mice><Mice Mammals><Modeling><Modern Man><Molecular><Murine><Mus><Mutation><Myocarditis><NS Proteins><Neurologic Manifestations><Neurologic Signs and Symptoms><Neurologic Symptoms><Neurological Manifestations><Neurological Signs and Symptoms><Neuropathogenesis><Oral><Palsy><Paralysed><Pathogenesis><Picornaviridae><Picornaviruses><Play><Plegia><Polio><Polio Virus><Poliomyelitis><Poliovirus><Polyproteins><Protein Methylases><Protein Methylation><Protein Methyltransferases><Proteins><Proteomics><RNA Viruses><RNA replication><Regulation><Rhinovirus><Rhinovirus infection><Role><Site><Structure><Subcellular Process><Testing><Therapeutic Intervention><Tissue Growth><Tissues><Translations><Transmission><Veterinary Medicine><Viral><Viral Diseases><Viral Nonstructural Proteins><Viral Pathogenesis><Viremia><Virus><Virus Diseases><Virus Replication><acute flaccid myelitis><asthma attack><asthma exacerbation><cardiac inflammation><cell type><cryo-EM><cryoEM><cryogenic electron microscopy><exacerbation in asthma><exacerbation prone asthma><exacerbation prone asthmatic><genome mutation><human disease><immune competent><in vivo><infected with Rhinovirus><infection mouth><innate immune mechanisms><insight><intervention therapy><kids><member><methylase><microbial><mouse model><murine model><neonate><neural><neural manifestation><new approaches><new drug target><new druggable target><new pharmacotherapy target><new therapeutic target><new therapy target><novel><novel approaches><novel drug target><novel druggable target><novel pharmacotherapy target><novel strategies><novel strategy><novel therapeutic target><novel therapy target><ontogeny><oral infection><oral infectious><paralysis><paralytic><pathogen><poliomyelitis virus><screening><screenings><social role><translation><transmethylase><transmission process><viraemia><viral RNA><viral infection><viral multiplication><viral replication><viral sepsis><virus RNA><virus host interaction><virus infection><virus multiplication><virus pathogenesis><virus-induced disease><virusemia><youngster>