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| Open AccessThe catalytic activity of TCPTP is auto-regulated by its intrinsically disordered tail and activated by Integrin alpha-1
TCPTP is a non-receptor type protein tyrosine phosphatase involved in various signalling pathways. Here, the authors provide structural insights into TCPTP activation, showing that TCPTP is inhibited by its C-terminal tail, which can be displaced by the cytosolic tail of integrin-α1, leading to activation.
- Jai Prakash Singh
- , Yang Li
- & Tzu-Ching Meng
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Article
| Open AccessStructural mechanism for tyrosine hydroxylase inhibition by dopamine and reactivation by Ser40 phosphorylation
Tyrosine hydroxylase (TH) catalyzes the rate-limiting step in the synthesis of the catecholamine neurotransmitters and hormones dopamine (DA), adrenaline and noradrenaline. Here, the authors present the cryo-EM structures of full-length human TH in the apo form and bound with DA, as well as the structure of Ser40 phosphorylated TH, and discuss the inhibitory and stabilizing effects of DA on TH and its counteraction by Ser40-phosphorylation.
- María Teresa Bueno-Carrasco
- , Jorge Cuéllar
- & José M. Valpuesta
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Article
| Open AccessStructural assessment of HLA-A2-restricted SARS-CoV-2 spike epitopes recognized by public and private T-cell receptors
Structural immunology is critical in understanding the interplay between the immune response and the infective agent but such studies in T cells and SARS-CoV-2 lag behind those of antibodies and B-cell receptors. Here the authors assess recognition of SARS-CoV-2 spike epitopes and their natural variants by public and private T cell receptors.
- Daichao Wu
- , Alexander Kolesnikov
- & Roy A. Mariuzza
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Article
| Open AccessCryo-EM demonstrates the in vitro proliferation of an ex vivo amyloid fibril morphology by seeding
Here, the authors present the cryo-EM structure of in vitro amyloid fibrils from recombinant SAA1.1 protein that were formed by seeding with fibrils purified from systemic AA amyloidosis tissue. This in vitro fibril structure resembles the structure of the ex vivo fibrils but differs from unseeded in vitro fibrils. These findings show that fibril morphologies can be propagated in vitro by seeding.
- Thomas Heerde
- , Matthies Rennegarbe
- & Marcus Fändrich
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Article
| Open AccessA method to construct the dynamic landscape of a bio-membrane with experiment and simulation
The authors present a strategy to construct dynamic biomolecular landscapes. Here, they derive a quantitative description of the distribution timescales and amplitudes of reorientational motion of POPC membranes from the combination of NMR relaxation data and frame analysis of MD simulations.
- Albert A. Smith
- , Alexander Vogel
- & Daniel Huster
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Article
| Open AccessConformational dynamics of the Beta and Kappa SARS-CoV-2 spike proteins and their complexes with ACE2 receptor revealed by cryo-EM
Here, the authors provide insights into the conformational dynamics of the Beta and Kappa SARS-CoV-2 spike (S) proteins by determining their cryo-EM structures, which revealed a distribution shift towards the open state for both variants compared to the wild-type S protein. They also present the structures of the Kappa and Beta S-ACE2 complexes, where a population shift towards the three receptor-binding domain up conformation was observed. In combination with biochemical data these structures show how the S protein variants efficiently recognize and bind to ACE2.
- Yifan Wang
- , Cong Xu
- & Yao Cong
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Article
| Open AccessStructure-guided bifunctional molecules hit a DEUBAD-lacking hRpn13 species upregulated in multiple myeloma
Rpn13 is a substrate receptor of the 26S proteasome and an anti-cancer drug target. Here, the authors identify and characterize XL5, a lead compound that binds to the N-terminal Pru domain of human Rpn13 (hRpn13), solve the NMR structure of XL5-ligated hRpn13 Pru and develop XL5-PROTACs that preferentially target an identified hRpn13 Pru fragment present in multiple myeloma cells.
- Xiuxiu Lu
- , Venkata R. Sabbasani
- & Kylie J. Walters
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Article
| Open AccessNanoparticles and photochemistry for native-like transmembrane protein footprinting
The intrinsic flexibility of membranes proteins still poses a challenge in determining their active structure. Here the authors describe the development of a method that combines chemical footprinting and mass spectrometry to assist in determining the structure of native membrane proteins and their dynamics.
- Jie Sun
- , Xiaoran Roger Liu
- & Michael L. Gross
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Article
| Open AccessTime-resolved cryo-EM visualizes ribosomal translocation with EF-G and GTP
EF-G drives ribosomal translocation along mRNA. Time-resolved cryo-EM captured translocation with EF-G•GTP—without inhibitors—revealing how EF-G uses ribosome fluctuations to drive translocation and GTP hydrolysis to leave at the right moment.
- Christine E. Carbone
- , Anna B. Loveland
- & Andrei A. Korostelev
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Article
| Open AccessHow to build a ribosome from RNA fragments in Chlamydomonas mitochondria
Mitoribosomes are remarkably diverse in their structures and compositions. Here the authors combine biochemistry, genetics, single particle cryo-electron microscopy and in situ cryo-electron tomography to reveal the mitochondrial ribosome of Chlamydomonas reinhardtii as an extreme example of evolution and species-specific adaptation.
- Florent Waltz
- , Thalia Salinas-Giegé
- & Yaser Hashem
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Article
| Open AccessStructural and molecular basis for Cardiovirus 2A protein as a viral gene expression switch
Many RNA viruses employ programmed –1 ribosomal frameshifting (PRF) to expand their coding capacity and optimize production of viral proteins. Here, the authors report structural and biophysical analysis of protein 2A from a cardiovirus, with insights into the mechanism of its PRF-stimulatory function.
- Chris H. Hill
- , Lukas Pekarek
- & Ian Brierley
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Article
| Open AccessHedgehog-Interacting Protein is a multimodal antagonist of Hedgehog signalling
Hedgehog-Interacting Protein (HHIP) is the only reported secreted inhibitor of Sonic Hedgehog (SHH) signalling. Here, the authors report structures of the HHIP N- and C-terminal domains, both in complexes with glycosaminoglycans, providing insights into the molecular basis for SHH sequestration and inhibition.
- Samuel C. Griffiths
- , Rebekka A. Schwab
- & Christian Siebold
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Article
| Open AccessBiphasic activation of β-arrestin 1 upon interaction with a GPCR revealed by methyl-TROSY NMR
β-arrestins commonly bind to two distinct elements in GPCRs: the phosphorylated carboxyl terminal tail (C tail) and the cytoplasmic face of the transmembrane region (TM core). Here, the authors use methyl-TROSY NMR measurements to characterise the interactions between β-arrestin 1 (βarr1) and a GPCR and observe that C tail-mediated interaction with a GPCR alone induces the partial activation of βarr1, whereas the TM core- and C tail-mediated interactions together stabilize the activated conformation of βarr1.
- Yutaro Shiraishi
- , Yutaka Kofuku
- & Ichio Shimada
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Article
| Open AccessSmall molecule modulation of the Drosophila Slo channel elucidated by cryo-EM
Slowpoke (Slo) channels are voltage-gated potassium channels that are activated by high intracellular Ca2+ concentrations, and they are targets for insecticides and antiparasitic drugs. Here, the authors present the cryo-EM structures of the Drosophila melanogaster Slo channel in the Ca2+-bound and Ca2+-free conformations, as well as in complex with the fungal neurotoxin verruculogen and the anthelmintic drug emodepside and discuss the mechanisms by which they affect the activity of Slo.
- Tobias Raisch
- , Andreas Brockmann
- & Stefan Raunser
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Article
| Open AccessStructural basis for transthyretin amyloid formation in vitreous body of the eye
Systemic ATTR amyloidosis causes the abnormal accumulation of ATTR fibrils formed from the human plasma protein transthyretin (TTR) in multiple organs including the eye. Here, the authors present a 3.2 Å cryo-EM structure of an ATTR fibril isolated from the vitreous body of an ATTR patient’s eye and discuss the mechanism for the structural conversion of TTR into a fibrillar form.
- Irina Iakovleva
- , Michael Hall
- & A. Elisabeth Sauer-Eriksson
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Article
| Open AccessSliding of HIV-1 reverse transcriptase over DNA creates a transient P pocket – targeting P-pocket by fragment screening
Here the authors observe a transient P-pocket created when HIV reverse transcriptase slides over DNA substrate, identify fragments targeting this pocket, and develop a cryo-EM platform for lead optimization.
- Abhimanyu K. Singh
- , Sergio E. Martinez
- & Kalyan Das
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Article
| Open AccessPlasticity within the barrel domain of BamA mediates a hybrid-barrel mechanism by BAM
The β-barrel assembly machinery (BAM) assists the folding and membrane insertion of bacterial outer membrane proteins. Here, the authors report structural characterization of BAM in lipid environment and in complex with the client protein EspP integrated into the barrel of BamA, providing insight into BAM mechanism of function.
- Runrun Wu
- , Jeremy W. Bakelar
- & Nicholas Noinaj
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Article
| Open AccessMolecular basis for redox control by the human cystine/glutamate antiporter system xc−
System xc- is a cystine transporter that is expressed in the plasma membrane and imports cystine in exchange for intracellular glutamate. Here, the authors present the cryo-EM structure of human system xc- both in the apo form and the glutamate bound state, and further supported by molecular dynamics and cell-based assays they discuss its cystine transport mechanism.
- Joanne L. Parker
- , Justin C. Deme
- & Simon Newstead
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Article
| Open AccesseIF2B-capturing viral protein NSs suppresses the integrated stress response
Here the authors show that a viral protein interferes with the binding of phosphorylated eIF2 to eIF2B, thereby suppressing the host integrated stress response (ISR). This suppression of the ISR abrogates translational changes of the host and ameliorates neurite degradation under stress.
- Kazuhiro Kashiwagi
- , Yuichi Shichino
- & Takuhiro Ito
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Article
| Open AccessStructural basis of reactivation of oncogenic p53 mutants by a small molecule: methylene quinuclidinone (MQ)
The tumor suppressor p53 is mutated in more than half of human cancers and the compound methylene quinuclidinone (MQ) was shown to reactivate p53 mutants by binding covalently to cysteine residues. Here, the authors present crystal structures of wild-type and cancer related p53 mutant core domains bound to MQ alone and in complex with their DNA response elements and observe that MQ is bound to several cysteine residues located at the surface of the core domain.
- Oksana Degtjarik
- , Dmitrij Golovenko
- & Zippora Shakked
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Article
| Open AccessDeepRank: a deep learning framework for data mining 3D protein-protein interfaces
The authors present DeepRank, a deep learning framework for the data mining of large sets of 3D protein-protein interfaces (PPI). They use DeepRank to address two challenges in structural biology: distinguishing biological versus crystallographic PPIs in crystal structures, and secondly the ranking of docking models.
- Nicolas Renaud
- , Cunliang Geng
- & Li C. Xue
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Article
| Open AccessMechanism of phosphate sensing and signaling revealed by rice SPX1-PHR2 complex structure
SPX proteins sense phosphate levels in plant cells by binding to inositol polyphosphates (InsP) and suppressing the activity of PHR transcription factors. Here the authors show that when bound to InsP6, the rice SPX1 protein inhibits the activity of PHR2 by attenuating both its dimerization and DNA binding activity.
- Jia Zhou
- , Qinli Hu
- & Weiman Xing
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Article
| Open AccessRegulation of the EphA2 receptor intracellular region by phosphomimetic negative charges in the kinase-SAM linker
Eph receptor tyrosine kinases and their ephrin ligands mediate cell-cell communication. Here, the authors assess the structure and dynamics of the EphA2 intracellular region and uncover complex effects of phosphorylation within the linker region between EphA2 kinase and SAM domains.
- Bernhard C. Lechtenberg
- , Marina P. Gehring
- & Elena B. Pasquale
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Article
| Open AccessDiscovery of an exosite on the SOCS2-SH2 domain that enhances SH2 binding to phosphorylated ligands
SOCS2 is a key regulator of growth hormone and cytokine signaling, which recognizes phosphotyrosine (pTyr)-modified targets via a central SH2 domain. Here, the authors discover and characterize an exosite on this SH2 domain that can bind a non-phosphorylated peptide to enhance SOCS2:pTyr affinity.
- Edmond M. Linossi
- , Kunlun Li
- & Sandra E. Nicholson
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Article
| Open AccessCatalytic flexibility of rice glycosyltransferase OsUGT91C1 for the production of palatable steviol glycosides
Steviol glycosides from the plant Stevia rebaudiana are already used as lowcalorie sweeteners, but the most abundant naturally occurring compounds have a bitter aftertaste. Here, the authors characterize and engineer rice glycosyltransferase OsUGT91C1 to facilitate the large-scale production of naturally rare but palatable glycosides Reb D and Reb M
- Jinzhu Zhang
- , Minghai Tang
- & Wei Cheng
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Article
| Open AccessConformational changes in Lassa virus L protein associated with promoter binding and RNA synthesis activity
The L protein of segmented, negative strand RNA viruses contains the RNA-dependent RNA polymerase essential for virus amplification. Here, the authors report cryoEM structures of the Lassa virus L protein in active, RNA-bound states, and provide mechanistic insights.
- Tomas Kouba
- , Dominik Vogel
- & Stephen Cusack
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Article
| Open AccessKinetic and structural mechanism for DNA unwinding by a non-hexameric helicase
UvrD is a model helicase from the non-hexameric Superfamily 1. Here, the authors use optical tweezers to measure directly the stepwise translocation of UvrD along a DNA hairpin, and propose a mechanism in which UvrD moves one base pair at a time, but sequesters the nascent single strands, releasing them after a variable number of ATP hydrolysis cycles.
- Sean P. Carney
- , Wen Ma
- & Yann R. Chemla
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Article
| Open AccessMechanism of Rad26-assisted rescue of stalled RNA polymerase II in transcription-coupled repair
Here the authors provide models of RNA polymerase II bound to the yeast CSB ortholog Rad26 in different nucleotide states; explain how Rad26 domain motions help the polymerase progress past DNA lesions; and interpret the effects of CSB-associated disease mutations.
- Chunli Yan
- , Thomas Dodd
- & Ivaylo Ivanov
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Article
| Open AccessMounting, structure and autocleavage of a type VI secretion-associated Rhs polymorphic toxin
Rearrangement hot spots (Rhs) proteins are bacterial polymorphic toxin systems. Here, the authors show that Rhs1 forms a complex with the Type VI secretion system (T6SS) spike protein VgrG and the EagR chaperone. They also present the cryo-EM structure of the Rhs1-EagR complex and propose a model for Rhs loading and delivery by the T6SS.
- Dukas Jurėnas
- , Leonardo Talachia Rosa
- & Eric Cascales
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Article
| Open AccessStructural basis for the E3 ligase activity enhancement of yeast Nse2 by SUMO-interacting motifs
Nse2 is a SUMO E3 ligase component of the Smc5/6 multisubunit complex involved in the DNA repair and chromosome integrity. Here, the structure of the Nse2 in complex with an E2-SUMO thioester mimetic reveals the combined action of two SIM motifs during the E3- dependent conjugation reaction.
- Nathalia Varejão
- , Jara Lascorz
- & David Reverter
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Article
| Open AccessCrystal structures of phosphatidyl serine synthase PSS reveal the catalytic mechanism of CDP-DAG alcohol O-phosphatidyl transferases
CDP-diacylglycerol (CDP-DAG) alcohol O-phosphatidyl transferases (CDP-APs) are conserved in archaea, bacteria, and eukaryotes and catalyze the de novo synthesis of phospho-lipids from the precursor CDP-DAG and an alcohol. Here, the authors present the crystal structures of the Methanocaldococcus jannaschii phosphatidyl serine synthase (MjPSS) in four different states and suggest a model for its catalytic mechanism.
- Martin Centola
- , Katharina van Pee
- & Özkan Yildiz
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Article
| Open AccessStructural basis of Ty3 retrotransposon integration at RNA Polymerase III-transcribed genes
Ty3 retrotransposon integrates with an exquisite specificity upstream of RNA Polymerase III-transcribed genes, such as transfer RNAs. Here the authors resolve a cryo-EM structure of an active Ty3 intasome in complex with a TFIIIB-bound tRNA promoter, shedding light into the molecular determinants of harmless retrotransposition.
- Guillermo Abascal-Palacios
- , Laura Jochem
- & Alessandro Vannini
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Article
| Open AccessMolecular architecture of black widow spider neurotoxins
The venom of Latrodectus spiders contains seven Latrotoxins (LaTXs), among them α-latrocrustatoxin (LCT) and δ- latroinsectotoxins δ-LIT. LaTXs bind to specific receptors on the surface of neuronal cells and target the molecular exocytosis machinery. Here, the authors present the cryo-EM structure of the α-LCT monomer and the δ-LIT dimer, which reveal that LaTXs are organized in four domains and they discuss the potential oligomerisation mechanism that takes place before LaTXs membrane insertion. Both recombinant α-LCT and δ-LIT form channels in artificial membrane bilayers, that are stabilized by Ca2+ ions.
- Minghao Chen
- , Daniel Blum
- & Christos Gatsogiannis
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Article
| Open AccessStructural insights into proteolytic activation of the human Dispatched1 transporter for Hedgehog morphogen release
Dispatched (Disp) RND transporter, activated by Furin-mediated proteolytic cleavage, mediates the release of the lipid-modified Hedgehog (Hh) ligands. Here, the authors report structures of human Disp1 (hDisp1) before and after cleavage, and in complex with lipid-modified Sonic hedgehog (Shh), with insights into the mechanisms of hDisp1 activation and function.
- Wanqiu Li
- , Linlin Wang
- & Xin Gong
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Article
| Open AccessStructural evolution of a DNA repair self-resistance mechanism targeting genotoxic secondary metabolites
Microbial DNA glycosylases associated with the biosynthesis of DNA-damaging antibiotics have evolved self-resistance for their cognate natural products. Here, the authors provide evidence that cellular self-resistance is enabled by reduced affinity of the glycosylases for the excision products of the corresponding DNA lesions.
- Elwood A. Mullins
- , Jonathan Dorival
- & Brandt F. Eichman
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Article
| Open AccessHelicobacter pylori FabX contains a [4Fe-4S] cluster essential for unsaturated fatty acid synthesis
Helicobacter pylori FabX, a dehydrogenase/isomerase flavoprotein, is required for unsaturated fatty acid synthesis. Here, the authors characterize FabX substrate recognition and catalytic mechanism, and reveal that it contains an atypical [4Fe-4S] cluster, which is essential and participates in the catalytic cycle.
- Jiashen Zhou
- , Lin Zhang
- & Liang Zhang
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Article
| Open AccessCryo-EM snapshots of a native lysate provide structural insights into a metabolon-embedded transacetylase reaction
How is acetyl-CoA produced in the context of the endogenous, eukaryotic pyruvate dehydrogenase complex metabolon? Here the authors dissect the embedded transacetylase reaction through biochemical, cryo-EM, HADDOCKing and molecular dynamics methods.
- Christian Tüting
- , Fotis L. Kyrilis
- & Panagiotis L. Kastritis
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Article
| Open AccessStructures of tweety homolog proteins TTYH2 and TTYH3 reveal a Ca2+-dependent switch from intra- to intermembrane dimerization
Tweety Homologs (TTYHs) are highly conserved membrane proteins, whose functions remain poorly understood. Here, the authors present the cryo-EM structures of murine TTYH2 and TTYH3 that form cis-dimers in the presence of Ca2+, whereas in the absence of Ca2+ TTYH2 adopts monomeric and trans-dimeric structures. The presented structures lack ion conducting pathways, which is consistent with results from electrophysiology measurements.
- Baobin Li
- , Christopher M. Hoel
- & Stephen G. Brohawn
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Article
| Open AccessStructure of HIV-1 Vpr in complex with the human nucleotide excision repair protein hHR23A
Vpr is a HIV-1 accessory virulence factor that also interacts with the human DNA repair protein hHR23A. Here, the authors present the structure of Vpr in complex with the C-terminal half of hHR23A comprising the XPC-binding and ubiquitin-associated domains, which reveals that hHR23A interacts with the DCAF1-binding and not the substrate-binding Vpr surface and further illustrates how Vpr acts as a versatile structural adapter that targets diverse DNA repair pathways.
- In-Ja L. Byeon
- , Guillermo Calero
- & Angela M. Gronenborn
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Article
| Open AccessStructural and functional analysis of the promiscuous AcrB and AdeB efflux pumps suggests different drug binding mechanisms
Resistance-nodulation-cell division (RND)-type tripartite efflux pumps confer multidrug resistance to Gram-negative bacteria. Here, structural and functional analyses of AdeB from Acinetobacter baumannii and AcrB from Escherichia coli provide insight into their different drug-binding and conformational drug transport states.
- Alina Ornik-Cha
- , Julia Wilhelm
- & Klaas M. Pos
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Article
| Open AccessA structured RNA motif locks Argonaute2:miR-122 onto the 5’ end of the HCV genome
The RNA genome of the Hepatitis C Virus binds to the liver-specific miR122. Here the authors report the crystal structure of the Ago2:miR122:HCV complex showing that the viral RNA’s structural element traps the Ago2:miR-122 complex on the 5’ end of the viral genome to protect it from degradation.
- Luca F. R. Gebert
- , Mansun Law
- & Ian J. MacRae
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Article
| Open AccessDevelopment of a BCL-xL and BCL-2 dual degrader with improved anti-leukemic activity,
Simultaneous targeting of BCL-xL and BCL-2 is an attractive approach for cancer treatment. Based on information gained by computational structure modelling, the authors develop a PROTAC that induces degradation of both BCL-xL and BCL-2 and effectively targets BCL-xL/2-dependent leukaemia cells.
- Dongwen Lv
- , Pratik Pal
- & Daohong Zhou
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Article
| Open AccessThe structural basis for the phospholipid remodeling by lysophosphatidylcholine acyltransferase 3
During phosphatidylcholine (PC) remodeling re-acylation is catalyzed by lysophosphatidylcholine acyltransferases (LPCAT). Here, the authors present crystal and cryo-EM structures of chicken LPCAT3 in the apo-, acyl donor-bound and acyl receptor-bound states, and based on the structures and further functional analysis they discuss the mechanism of the enzyme.
- Qing Zhang
- , Deqiang Yao
- & Yu Cao
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Article
| Open AccessArchitecture of the outer-membrane core complex from a conjugative type IV secretion system
DNA transfer between two bacterial cells is mediated by the conjugative type 4 secretion systems (T4SSs). Here, the authors report the structure of a complete T4SS outer-membrane core complex (OMCC), revealing distinct C17 and C13 symmetries of its central inner and peripheral outer ring regions, respectively.
- Himani Amin
- , Aravindan Ilangovan
- & Tiago R. D. Costa
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Article
| Open AccessN-terminal tyrosine of ISCU2 triggers [2Fe-2S] cluster synthesis by ISCU2 dimerization
[2Fe-2S] protein cofactors are essential for life and are synthesized on ISCU2 scaffolds. Here, the authors show that hydrophobic interaction of two conserved N-terminal tyrosines induces ISCU2 dimerization and concomitant [2Fe-2S] cluster synthesis.
- Sven-A. Freibert
- , Michal T. Boniecki
- & Roland Lill
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Article
| Open AccessCryo-EM structures of intermediates suggest an alternative catalytic reaction cycle for cytochrome c oxidase
Cytochrome c oxidase is a fundamental enzyme of life and its mechanism is not fully understood yet. Here, the authors present four cryo-EM structures of different intermediate states, which suggest an alternative cytochrome c oxidase reaction cycle.
- F. Kolbe
- , S. Safarian
- & H. Michel
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Article
| Open AccessStructure of the class C orphan GPCR GPR158 in complex with RGS7-Gβ5
The orphan GPR158 receptor belongs to the class C GPCR family and interacts with the regulator of G protein signaling 7 (RGS7)-Gβ5 complex. Here, the authors present the cryo-EM structure of human GPR158, which reveals that the extracellular domain contains a PAS domain, and they also determine the structures of GPR158 in complex with either one or two RGS7-Gβ5 heterodimers and discuss implications for the signaling mechanism.
- Eunyoung Jeong
- , Yoojoong Kim
- & Yunje Cho
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Article
| Open AccessHuman RIPK3 maintains MLKL in an inactive conformation prior to cell death by necroptosis
The pseudokinase MLKL is activated by the upstream kinase RIPK3 in the necroptotic pathway but the structural basis of MLKL activation is not well understood yet. Here, the authors present the crystal structures of the human RIPK3:MLKL complex and human RIPK3 kinase alone, which reveal structural differences between human and murine RIPK3 and they discuss mechanistic implications.
- Yanxiang Meng
- , Katherine A. Davies
- & James M. Murphy
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Article
| Open AccessPhosphorylation activates the yeast small heat shock protein Hsp26 by weakening domain contacts in the oligomer ensemble
Small heat shock proteins (sHsps) form large spherical assemblies and their regulation is not well understood. Here, the authors provide insights into the mechanism of Hsp26 activation by characterising phospho-mimetic mutants of yeast Hsp26. They present cryo-EM structures of the wild-type Hsp26 40mer and its phospho-mimetic mutants that reveal the location of the thermosensor in the oligomer, and the authors also show that the thermosensor domain is targeted by phosphorylation, which relieves the intrinsic inhibition of chaperone activity.
- Moritz Mühlhofer
- , Carsten Peters
- & Johannes Buchner