Macroautophagy(referred to as autophagy hereafter)is a major intracellular lysosomal degradation pathway that is responsible for the degradation of misfolded/damaged proteins and organelles.Previous studies showed tha...Macroautophagy(referred to as autophagy hereafter)is a major intracellular lysosomal degradation pathway that is responsible for the degradation of misfolded/damaged proteins and organelles.Previous studies showed that autophagy protects against acetaminophen(APAP)-induced injury(AILI)via selective removal of damaged mitochondria and APAP protein adducts.The lysosome is a critical organelle sitting at the end stage of autophagy for autophagic degradation via fusion with autophagosomes.In the present study,we showed that transcription factor EB(TFEB),a master transcription factor for lysosomal biogenesis,was impaired by APAP resulting in decreased lysosomal biogenesis in mouse livers.Genetic loss-of and gain-of function of hepatic TFEB exacerbated or protected against AILI,respectively.Mechanistically,overexpression of TFEB increased clearance of APAP protein adducts and mitochondria biogenesis as well as SQSTM1/p62-dependent non-canonical nuclear factor erythroid 2-related factor 2(NRF2)activation to protect against AILI.We also performed an unbiased cell-based imaging high-throughput chemical screening on TFEB and identified a group of TFEB agonists.Among these agonists,salinomycin,an anticoccidial and antibacterial agent,activated TFEB and protected against AILI in mice.In conclusion,genetic and pharmacological activating TFEB may be a promising approach for protecting against AILI.展开更多
Haloacetamides（HAMs） are cytotoxic, genotoxic, and mutagenic byproducts of drinking water disinfection. They are soft electrophilic compounds that form covalent bonds with the free thiol/thiolate in cysteine residue...Haloacetamides（HAMs） are cytotoxic, genotoxic, and mutagenic byproducts of drinking water disinfection. They are soft electrophilic compounds that form covalent bonds with the free thiol/thiolate in cysteine residues through an S_N2 reaction mechanism.Toxicity of the monohalogenated HAMs（iodoacetamide, IAM; bromoacetamide, BAM;or chloroacetamide, CAM） varied depending on the halogen substituent. The aim of this research was to investigate how the halogen atom affects the reactivity and toxicological properties of HAMs, measured as induction of oxidative/electrophilic stress response and genotoxicity. Additionally, we wanted to determine how well in silico estimates of electrophilic softness matched thiol/thiolate reactivity and in vitro toxicological endpoints.Each of the HAMs significantly induced nuclear Rad51 accumulation and ARE signaling activity compared to a negative control. The rank order of effect was IAM 〉 BAM 〉 CAM for Rad51, and BAM ≈ IAM 〉 CAM for ARE. In general, electrophilic softness and in chemico thiol/thiolate reactivity provided a qualitative indicator of toxicity, as the softer electrophiles IAM and BAM were more thiol/thiolate reactive and were more toxic than CAM.展开更多
The Zika virus(ZIKV)and dengue virus(DENV)flaviviruses exhibit similar replicative processes but have distinct clinical outcomes.A systematic understanding of virus–host protein–protein interaction networks can reve...The Zika virus(ZIKV)and dengue virus(DENV)flaviviruses exhibit similar replicative processes but have distinct clinical outcomes.A systematic understanding of virus–host protein–protein interaction networks can reveal cellular pathways critical to viral replication and disease pathogenesis.Here we employed three independent systems biology approaches toward this goal.First,protein array analysis of direct interactions between individual ZIKV/DENV viral proteins and20,240 human proteins revealed multiple conserved cellular pathways and protein complexes,including proteasome complexes.Second,an RNAi screen of 10,415 druggable genes identified the host proteins required for ZIKV infection and uncovered that proteasome proteins were crucial in this process.Third,high-throughput screening of 6016 bioactive compounds for ZIKV inhibition yielded 134 effective compounds,including six proteasome inhibitors that suppress both ZIKV and DENV replication.Integrative analyses of these orthogonal datasets pinpoint proteasomes as critical host machinery for ZIKV/DENV replication.Our study provides multi-omics datasets for further studies of flavivirus–host interactions,disease pathogenesis,and new drug targets.展开更多
基金We would like to thank Dr.Thomas Ru¨licke at Department of Biomedical Sciences,University of Veterinary Medicine Vienna,Vienna,Austria and Dr.Kurt Zatloukal at The Institute of Pathology,Medical University of Graz,A-8036 Graz,Austria for providing us whole body Sqstm1/p62 knockout mice for the hepatocyte isolation experiment.We also thank Larysa Stroganova at University of Kansas Medical Center for her excellent assistance for the EM studies.This study was supported in part by the National Institute of Health(NIH,USA)funds R01 DK102142,R01 AG072895,R37 AA020518(WXD)and in part by the Intramural Research Program of the National Center for Advancing Translational Sciences,NIH(USA).
文摘Macroautophagy(referred to as autophagy hereafter)is a major intracellular lysosomal degradation pathway that is responsible for the degradation of misfolded/damaged proteins and organelles.Previous studies showed that autophagy protects against acetaminophen(APAP)-induced injury(AILI)via selective removal of damaged mitochondria and APAP protein adducts.The lysosome is a critical organelle sitting at the end stage of autophagy for autophagic degradation via fusion with autophagosomes.In the present study,we showed that transcription factor EB(TFEB),a master transcription factor for lysosomal biogenesis,was impaired by APAP resulting in decreased lysosomal biogenesis in mouse livers.Genetic loss-of and gain-of function of hepatic TFEB exacerbated or protected against AILI,respectively.Mechanistically,overexpression of TFEB increased clearance of APAP protein adducts and mitochondria biogenesis as well as SQSTM1/p62-dependent non-canonical nuclear factor erythroid 2-related factor 2(NRF2)activation to protect against AILI.We also performed an unbiased cell-based imaging high-throughput chemical screening on TFEB and identified a group of TFEB agonists.Among these agonists,salinomycin,an anticoccidial and antibacterial agent,activated TFEB and protected against AILI in mice.In conclusion,genetic and pharmacological activating TFEB may be a promising approach for protecting against AILI.
基金partial support from the U.S.Army Engineer Research and Development Center and the Army Environmental Quality Technology program, CESU W9132T-16-2-0005 (MJP)partly supported by the interagency agreement IAG #NTR 12003 from the National Institute of Environmental Health Sciences/Division of the National Toxicology Program to the National Center for Advancing Translational Sciences, National Institutes of Health
文摘Haloacetamides（HAMs） are cytotoxic, genotoxic, and mutagenic byproducts of drinking water disinfection. They are soft electrophilic compounds that form covalent bonds with the free thiol/thiolate in cysteine residues through an S_N2 reaction mechanism.Toxicity of the monohalogenated HAMs（iodoacetamide, IAM; bromoacetamide, BAM;or chloroacetamide, CAM） varied depending on the halogen substituent. The aim of this research was to investigate how the halogen atom affects the reactivity and toxicological properties of HAMs, measured as induction of oxidative/electrophilic stress response and genotoxicity. Additionally, we wanted to determine how well in silico estimates of electrophilic softness matched thiol/thiolate reactivity and in vitro toxicological endpoints.Each of the HAMs significantly induced nuclear Rad51 accumulation and ARE signaling activity compared to a negative control. The rank order of effect was IAM 〉 BAM 〉 CAM for Rad51, and BAM ≈ IAM 〉 CAM for ARE. In general, electrophilic softness and in chemico thiol/thiolate reactivity provided a qualitative indicator of toxicity, as the softer electrophiles IAM and BAM were more thiol/thiolate reactive and were more toxic than CAM.
基金supported by the National Institutes of Health(NIH),USA(Grant Nos.U19AI131130,R01GM111514,R21AI131706,R35NS097370,and R37NS047344)the Intramural Research Program of the NCATS/NIH,USA
文摘The Zika virus(ZIKV)and dengue virus(DENV)flaviviruses exhibit similar replicative processes but have distinct clinical outcomes.A systematic understanding of virus–host protein–protein interaction networks can reveal cellular pathways critical to viral replication and disease pathogenesis.Here we employed three independent systems biology approaches toward this goal.First,protein array analysis of direct interactions between individual ZIKV/DENV viral proteins and20,240 human proteins revealed multiple conserved cellular pathways and protein complexes,including proteasome complexes.Second,an RNAi screen of 10,415 druggable genes identified the host proteins required for ZIKV infection and uncovered that proteasome proteins were crucial in this process.Third,high-throughput screening of 6016 bioactive compounds for ZIKV inhibition yielded 134 effective compounds,including six proteasome inhibitors that suppress both ZIKV and DENV replication.Integrative analyses of these orthogonal datasets pinpoint proteasomes as critical host machinery for ZIKV/DENV replication.Our study provides multi-omics datasets for further studies of flavivirus–host interactions,disease pathogenesis,and new drug targets.
