Towards high-resolution structural biology of membrane protein complexes in their native lipid environment

NIH Pandemic-Era Grants

Pandemic Era Grants

2021

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Principal Investigator: Doreen  Matthies
Organization: EUNICE KENNEDY SHRIVER NATIONAL INSTITUTE OF CHILD HEALTH & HUMAN DEVELOPMENT
Fiscal Year: 2021
Award: $987,868
Funding agency: Eunice Kennedy Shriver National Institute of Child Health and Human Development

(1)	Structural and functional investigation of CXCR3 chemokine receptor in its role in recurrent miscarriage
Recurrent miscarriage (RM) is usually defined as the loss of three or more consecutive pregnancies prior to the 20th week of gestation affecting approximately 1% of women of reproductive age. 50% of cases of RM is unknown but there is evidence supporting immune causes, more specifically that a T helper (Th) 1-type response is associated with the pathogenesis of RM. RM woman show higher ratios of Th1 (CXCR3 and CCR5) to Th2 (CCR3 and CCR4) chemokine receptors. A Th1-type reaction in the maternofetal interface mainly triggers an inflammatory response, while a Th2-type reaction typically promotes growth of trophoblastic cells which is beneficial for successful maintenance of a pregnancy.
Incoming postdoc Dr. Munazza Shahid will study the structure and function of CXCR3 chemokine receptor alone and in complex with its ligands (CXCL4, CXCL9, CXCL10 and CXCL11) to work towards a treatment to prevent pregnancy loss in women with RM.

(2)	Structure and function of magnesium channel Mrs2
Mrs2 is the eukaryotic homolog of bacterial magnesium channel CorA. CorA forms a homo-pentameric channel which forms a symmetric closed state at normal to high concentrations of magnesium with magnesium binding sites between protomers as well as near the membrane pore. Under low magnesium concentrations the channel undergoes an asymmetric opening likely caused by the destabilization of protomer interactions when magnesium ions dissociate from their binding site. Incoming postdoc Dr. Louis Lai will expand research on magnesium channels by looking at eukaryotic magnesium channel Mrs2 which is located in the inner mitochondrial membrane. Structural studies in synthetic as well as native nanodiscs as well as liposomes are planned to investigate the structure and mechanism of this eukaryotic channel.

(3)	Structural determination of full-length SARS-CoV-2 spike protein and drug development
COVID-19 caused by the SARS-CoV-2 virus has posed a global threat since it was first identified end of 2019. The rapid development of vaccines helped to counteract the rapid spread of COVID-19. However, vaccines for children under the age of 12 have not yet been approved. More children have been infected by more contagious variants of the virus and the recent surge of COVID-19 cases has put an unprecedented pressure on the pediatric health care system. 
The SARS-Cov-2 spike protein is responsible for the initial binding of the virus to the receptor ACE2 on human cells. Better understanding of the function and structure of the spike protein is critical for development of both primary prevention such as vaccine, and therapeutic treatments to combat the COVID-19 pandemic. Structures of the spike proteins soluble ectodomain have been determined but the full-length spike including its membrane domain has not been well studied. We are working towards determining the structures of full-length spike protein and identify the key vaccine and drug binding interfaces in order to develop treatments that block viral entry into human cells with high efficiency and specificity which are also safe for children. We have successfully cloned and expressed the full-length spike protein, and we are working towards high-resolution structural determination of different variants and complexes.

(4)	Structural investigation of inner mitochondrial membrane supercomplex II and III
As the powerhouses of cells, mitochondria provide energy in form of ATP for most of the cellular activities. There are five essential protein complexes located on the inner mitochondrial membrane which carry out one of the most important reaction in the cells  oxidative phosphorylation, which generates ATP. Functions of these protein complexes have been extensively studied and crystal structures of individual complexes have been determined. It is proposed that protein complexes of the respiratory chain can associate and form of supercomplexes or respirasomes. Among these five protein complexes, cytochrome bc1, also known as complex III, is a central component of the cellular respiratory chain. It catalyzes electron transfer from quinol to cytochrome c and couples this electron transfer process to proton translocation across the membrane. Mitochondrial Complex II, also called succinate dehydrogenase, is another important protein complex within the mitochondrial electron transfer chain. It oxidizes succinate from the Krebs-cycle to fumarate and reduces ubiquinone to ubiquinol. Previous studies have proposed the formation of a supercomplex between complex II and complex III, which has been confirmed by biochemical analyses of scientist Dr. Fei Zhou. We are currently working towards solving the structure of this supercompex by Single-Particle Cryo-EM. Together with biochemical data, the structure of supercompex II and III will reveal detailed information of electron transfer between the Krebs-cycle and the respiratory chain and could shed light on the biogenesis and treatment of many human diseases related to respiratory chain deficiency such as delayed child development, autism, tumorigenesis and aging. 


(5)	Collaborations
Collaborations involving structural and computational studies on a variety of membrane proteins including transporters, channels, and receptors as well as viral spike protein conformations in different cellular compartments, virus-like-particle (VLP), SARS-CoV-2 accessory membrane protein, extracellular vesicles and lipid transport across cells, as well as testing new detergents and polymers to gently extract membrane protein complexes from their native lipid environment for high-resolution structural studies.

Terms: <0-11 years old><2019 novel corona virus><2019 novel coronavirus><2019-nCoV><2019-nCoV S protein><2019-nCoV spike glycoprotein><2019-nCoV spike protein><ACE2><Affect><Age><Aging><Autism><Autistic Disorder><Binding><Binding Sites><Biochemical><Biochemistry><Biogenesis><Biological><Biological Chemistry><Body Tissues><C-C CKR-5><C-C CKR-5 Gene><C-C Chemokine Receptor Type 5><C-C Chemokine Receptor Type 5 Gene><CC Chemokine Receptor 5><CC-CKR-5><CC-CKR-5 Gene><CC-CKR5><CCCKR5><CCCKR5 Gene><CCR-5><CCR-5 Gene><CCR5><CCR5 Protein><CCR5 Receptors><CCR5 gene><CD183><CD195 Antigen><CD195 Antigen Gene><CHEMR13><CHEMR13 Gene><CKR-5><CKR-5 Gene><CKR-L2><CKR5><CKR5 Gene><CKR5 Receptors><CMKAR3><CMKBR5><CMKBR5 Gene><COVID crisis><COVID epidemic><COVID pandemic><COVID-19><COVID-19 S protein><COVID-19 crisis><COVID-19 epidemic><COVID-19 global health crisis><COVID-19 global pandemic><COVID-19 health crisis><COVID-19 pandemic><COVID-19 public health crisis><COVID-19 spike glycoprotein><COVID-19 spike protein><COVID-19 virus><COVID19><COVID19 S protein><COVID19 crisis><COVID19 epidemic><COVID19 global health crisis><COVID19 global pandemic><COVID19 health crisis><COVID19 pandemic><COVID19 public health crisis><COVID19 spike glycoprotein><COVID19 spike protein><COVID19 virus><CRG-2><CV-19><CV19><CXCL10><CXCL10 gene><CXCL11><CXCL11 gene><CXCL9><CXCL9 gene><CXCR3><CXCR3 gene><Cell Body><Cell Membrane Lipids><Cells><Chemokine (C-C Motif) Receptor 5><Chemokine (C-C) Receptor 5><Chemokine (C-C) Receptor 5 Gene><Chemokine (C-X-C Motif) Receptor 3><Chemokine Receptor Gene><Child><Child Development><Child Youth><Childhood><Children (0-21)><Citric Acid Cycle><CoV-2><CoV2><Coenzyme Q><Coenzyme Q-Cytochrome-c Reductase><Coenzyme QH2-Cytochrome-c Reductase><Collaborations><Combining Site><Complex><Complex III><Controlled Environment><Couples><Cryo-electron Microscopy><Cryo-electron tomography><Cryoelectron Microscopy><Crystallization><Cytochrome b-c2 Oxidoreductase><Cytochrome bc1><Cytochrome bc1 Complex><DNA Molecular Biology><Data><Detergents><Development><Dihydroubiquinone-Cytochrome-c Reductase><Drugs><Early Infantile Autism><Electron Cryomicroscopy><Electron Microscopy><Electron Transport><Electron Transport Complex III><Environment><Ferricytochrome c><Ferrocytochrome c><Fumarate Reductase><Fumarates><G Protein-Coupled Receptor 9><GPR9><GeneHomolog><Generalized Growth><Gestation><Goals><Growth><H+ element><H174><HIV-1 Fusion Co-Receptor><HIV-1 Fusion Co-Receptor Gene><Habitual Abortion><Health Care Systems><Healthcare Systems><Homo><Homolog><Homologous Gene><Homologue><Human><Humig><Hydrogen Ions><Hydroquinones><I-TAC><IFI10><INP10><IP-10><IP-9><IP10><IP10 Receptor><IP10-Mig receptor><IP10-R><IP9><Immune><Immunes><Individual><Infant and Child Development><Infantile Autism><Inflammatory Response><Inner mitochondrial membrane><Investigation><Ions><Kanner's Syndrome><Krebs Cycle><Length><Ligands><Light><Lipid Trafficking><Lipids><Liposomal><Liposomes><MIG Gene><MOB-1><Magnesium><Maintenance><Medication><Membrane><Membrane Lipids><Membrane Protein Gene><Membrane Proteins><Membrane Structure and Function><Membrane-Associated Proteins><Methods><Mg element><Mg++ element><Micelles><Microscopy><Mig Receptor><Mig-R><MigR><Mitochondria><Mitochondrial Respiratory Chain Deficiencies><Modern Man><Molecular Biology><Molecular Interaction><Molecular Transport><Morphology><Oncogenesis><Origin of Life><Oxidative Phosphorylation><Oxidative Phosphorylation Pathway><Oxides><Pathogenesis><Pharmaceutic Preparations><Pharmaceutical Preparations><Photoradiation><Polymers><Postdoc><Postdoctoral Fellow><Pregnancy><Pregnancy loss><Primary Prevention><Process><Protein Conformation><Proteins><Protomer><Protons><QH(2)-Cytochrome-c Reductase><QH(2)-Ferricytochrome-c Oxidoreductase><Quinols><Reaction><Reactive Site><Receptor Protein><Recurrent Abortion><Recurrent Miscarriage><Research><Research Associate><Resolution><Respiratory Chain><Respiratory Chain Deficiency><Role><SARS corona virus 2><SARS-CoV-2><SARS-CoV-2 S protein><SARS-CoV-2 epidemic><SARS-CoV-2 global health crisis><SARS-CoV-2 global pandemic><SARS-CoV-2 pandemic><SARS-CoV-2 spike glycoprotein><SARS-CoV-2 spike protein><SARS-CoV2><SARS-CoV2 S protein><SARS-CoV2 epidemic><SARS-CoV2 pandemic><SARS-CoV2 spike glycoprotein><SARS-CoV2 spike protein><SARS-associated corona virus 2><SARS-associated coronavirus 2><SARS-coronavirus-2><SARS-coronavirus-2 epidemic><SARS-coronavirus-2 pandemic><SARS-related corona virus 2><SARS-related coronavirus 2><SARSCoV2><SCYB10><SCYB11><SCYB9><SCYB9B><Scanning Electron Microscopy><Scientist><Severe Acute Respiratory Distress Syndrome CoV 2><Severe Acute Respiratory Distress Syndrome Corona Virus 2><Severe Acute Respiratory Distress Syndrome Coronavirus 2><Severe Acute Respiratory Syndrome CoV 2><Severe Acute Respiratory Syndrome CoV 2 epidemic><Severe Acute Respiratory Syndrome CoV 2 pandemic><Severe Acute Respiratory Syndrome-associated coronavirus 2><Severe Acute Respiratory Syndrome-related coronavirus 2><Severe acute respiratory syndrome associated corona virus 2><Severe acute respiratory syndrome corona virus 2><Severe acute respiratory syndrome coronavirus 2><Severe acute respiratory syndrome coronavirus 2 S protein><Severe acute respiratory syndrome coronavirus 2 epidemic><Severe acute respiratory syndrome coronavirus 2 pandemic><Severe acute respiratory syndrome coronavirus 2 spike glycoprotein><Severe acute respiratory syndrome coronavirus 2 spike protein><Severe acute respiratory syndrome related corona virus 2><Shapes><Specificity><Structure><Succinate Dehydrogenase><Succinates><Succinic Dehydrogenase><Succinic Oxidase><Surface Proteins><TCA cycle><Techniques><Testing><Therapeutic><Tissue Growth><Tissues><Transport Process><Tricarboxylic Acid Cycle><Trophoblastic Cell><Ubihydroquinone-Cytochrome-c Reductase><Ubiquinol-Cytochrome-c Reductase><Ubiquinol-ferricytochrome-c oxidoreductase><Ubiquinone><Ubiquinone-Cytochrome b-c2 Oxidoreductase><Vaccines><Variant><Variation><Vesicle><Viral><Virus><Virus-like particle><Woman><Work><Wuhan coronavirus><ages><angiotensin converting enzyme 2><angiotensin converting enzyme II><artificial environment><autism spectrum disorder><autistic spectrum disorder><b-R1><biophysical approaches><biophysical methodology><biophysical methods><biophysical techniques><block viral entry><chemokine receptor><chronic spontaneous abortion><combat><computational studies><computer studies><corona virus disease 2019><corona virus disease 2019 epidemic><corona virus disease 2019 pandemic><coronavirus disease 2019><coronavirus disease 2019 S protein><coronavirus disease 2019 crisis><coronavirus disease 2019 epidemic><coronavirus disease 2019 global health crisis><coronavirus disease 2019 global pandemic><coronavirus disease 2019 health crisis><coronavirus disease 2019 pandemic><coronavirus disease 2019 public health crisis><coronavirus disease 2019 spike glycoprotein><coronavirus disease 2019 spike protein><coronavirus disease 2019 virus><coronavirus disease crisis><coronavirus disease epidemic><coronavirus disease pandemic><crg-10><cryo-EM><cryo-EM tomography><cryoEM><cryoEM tomography><cryoelectron tomography><cytochrome c><develop a vaccine><development of a vaccine><developmental><drug development><drug/agent><electron cryo-tomography><electron transfer><extracellular vesicles><fumarate hydrogenase><gIP-10><hCoV19><human disease><inhibit viral entry><light microscopy><lipid transport><magnesium ion><membrane structure><mitochondrial><nCoV2><nano disk><nanodisk><ontogeny><p-Dihydroxybenzenes><para-Dihydroxybenzenes><particle><pediatric><post-doc><post-doctoral><pressure><prevent><preventing><programs><protein complex><protein function><protein structure><protein structures><proteins structure><receptor><reproductive><response><severe acute respiratory syndrome coronavirus 2 global health crisis><severe acute 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