12 results on '"Ministry of Education Key Laboratory of Protein Sciences"'
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2. In situ structure of the red algal phycobilisome-PSII-PSI-LHC megacomplex.
- Author
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You X, Zhang X, Cheng J, Xiao Y, Ma J, Sun S, Zhang X, Wang HW, and Sui SF
- Subjects
- Energy Transfer, Photosynthesis, Cryoelectron Microscopy, Single Molecule Imaging, Light-Harvesting Protein Complexes chemistry, Light-Harvesting Protein Complexes metabolism, Light-Harvesting Protein Complexes ultrastructure, Photosystem I Protein Complex chemistry, Photosystem I Protein Complex metabolism, Photosystem I Protein Complex ultrastructure, Photosystem II Protein Complex chemistry, Photosystem II Protein Complex metabolism, Photosystem II Protein Complex ultrastructure, Phycobilisomes chemistry, Phycobilisomes metabolism, Phycobilisomes ultrastructure, Porphyridium chemistry, Porphyridium enzymology, Porphyridium metabolism, Porphyridium ultrastructure
- Abstract
In oxygenic photosynthetic organisms, light energy is captured by antenna systems and transferred to photosystem II (PSII) and photosystem I (PSI) to drive photosynthesis
1,2 . The antenna systems of red algae consist of soluble phycobilisomes (PBSs) and transmembrane light-harvesting complexes (LHCs)3 . Excitation energy transfer pathways from PBS to photosystems remain unclear owing to the lack of structural information. Here we present in situ structures of PBS-PSII-PSI-LHC megacomplexes from the red alga Porphyridium purpureum at near-atomic resolution using cryogenic electron tomography and in situ single-particle analysis4 , providing interaction details between PBS, PSII and PSI. The structures reveal several unidentified and incomplete proteins and their roles in the assembly of the megacomplex, as well as a huge and sophisticated pigment network. This work provides a solid structural basis for unravelling the mechanisms of PBS-PSII-PSI-LHC megacomplex assembly, efficient energy transfer from PBS to the two photosystems, and regulation of energy distribution between PSII and PSI., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)- Published
- 2023
- Full Text
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3. Structural insights into dsRNA processing by Drosophila Dicer-2-Loqs-PD.
- Author
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Su S, Wang J, Deng T, Yuan X, He J, Liu N, Li X, Huang Y, Wang HW, and Ma J
- Subjects
- Adenosine Triphosphate, Animals, Binding Sites, Phosphates metabolism, Protein Conformation, Cryoelectron Microscopy, Drosophila Proteins chemistry, Drosophila Proteins metabolism, Drosophila Proteins ultrastructure, Drosophila melanogaster, RNA Helicases chemistry, RNA Helicases metabolism, RNA Helicases ultrastructure, RNA, Double-Stranded chemistry, RNA, Double-Stranded metabolism, RNA, Double-Stranded ultrastructure, RNA, Small Interfering chemistry, RNA, Small Interfering metabolism, RNA, Small Interfering ultrastructure, RNA-Binding Proteins chemistry, RNA-Binding Proteins metabolism, RNA-Binding Proteins ultrastructure, Ribonuclease III chemistry, Ribonuclease III metabolism, Ribonuclease III ultrastructure
- Abstract
Small interfering RNAs (siRNAs) are the key components for RNA interference (RNAi), a conserved RNA-silencing mechanism in many eukaryotes
1,2 . In Drosophila, an RNase III enzyme Dicer-2 (Dcr-2), aided by its cofactor Loquacious-PD (Loqs-PD), has an important role in generating 21 bp siRNA duplexes from long double-stranded RNAs (dsRNAs)3,4 . ATP hydrolysis by the helicase domain of Dcr-2 is critical to the successful processing of a long dsRNA into consecutive siRNA duplexes5,6 . Here we report the cryo-electron microscopy structures of Dcr-2-Loqs-PD in the apo state and in multiple states in which it is processing a 50 bp dsRNA substrate. The structures elucidated interactions between Dcr-2 and Loqs-PD, and substantial conformational changes of Dcr-2 during a dsRNA-processing cycle. The N-terminal helicase and domain of unknown function 283 (DUF283) domains undergo conformational changes after initial dsRNA binding, forming an ATP-binding pocket and a 5'-phosphate-binding pocket. The overall conformation of Dcr-2-Loqs-PD is relatively rigid during translocating along the dsRNA in the presence of ATP, whereas the interactions between the DUF283 and RIIIDb domains prevent non-specific cleavage during translocation by blocking the access of dsRNA to the RNase active centre. Additional ATP-dependent conformational changes are required to form an active dicing state and precisely cleave the dsRNA into a 21 bp siRNA duplex as confirmed by the structure in the post-dicing state. Collectively, this study revealed the molecular mechanism for the full cycle of ATP-dependent dsRNA processing by Dcr-2-Loqs-PD., (© 2022. The Author(s).)- Published
- 2022
- Full Text
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4. Cryo-EM structures of apo and antagonist-bound human Ca v 3.1.
- Author
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Zhao Y, Huang G, Wu Q, Wu K, Li R, Lei J, Pan X, and Yan N
- Subjects
- Allosteric Regulation drug effects, Amino Acid Motifs, Amino Acid Sequence, Apoproteins genetics, Binding Sites, Calcium Channel Blockers pharmacology, Calcium Channels, T-Type genetics, Humans, Models, Molecular, Piperidines pharmacology, Protein Binding, Protein Conformation, Sequence Deletion, Apoproteins chemistry, Apoproteins ultrastructure, Calcium Channel Blockers chemistry, Calcium Channels, T-Type chemistry, Calcium Channels, T-Type ultrastructure, Cryoelectron Microscopy, Piperidines chemistry
- Abstract
Among the ten subtypes of mammalian voltage-gated calcium (Ca
v ) channels, Cav 3.1-Cav 3.3 constitute the T-type, or the low-voltage-activated, subfamily, the abnormal activities of which are associated with epilepsy, psychiatric disorders and pain1-5 . Here we report the cryo-electron microscopy structures of human Cav 3.1 alone and in complex with a highly Cav 3-selective blocker, Z9446,7 , at resolutions of 3.3 Å and 3.1 Å, respectively. The arch-shaped Z944 molecule reclines in the central cavity of the pore domain, with the wide end inserting into the fenestration on the interface between repeats II and III, and the narrow end hanging above the intracellular gate like a plug. The structures provide the framework for comparative investigation of the distinct channel properties of different Cav subfamilies.- Published
- 2019
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5. Modulation of cardiac ryanodine receptor 2 by calmodulin.
- Author
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Gong D, Chi X, Wei J, Zhou G, Huang G, Zhang L, Wang R, Lei J, Chen SRW, and Yan N
- Subjects
- Adenosine Triphosphate metabolism, Animals, Apoproteins metabolism, Binding Sites, Caffeine metabolism, Calcium metabolism, Cryoelectron Microscopy, Humans, Models, Molecular, Reproducibility of Results, Ryanodine Receptor Calcium Release Channel chemistry, Swine, Calmodulin metabolism, Ryanodine Receptor Calcium Release Channel metabolism
- Abstract
The high-conductance intracellular calcium (Ca
2+ ) channel RyR2 is essential for the coupling of excitation and contraction in cardiac muscle. Among various modulators, calmodulin (CaM) regulates RyR2 in a Ca2+ -dependent manner. Here we reveal the regulatory mechanism by which porcine RyR2 is modulated by human CaM through the structural determination of RyR2 under eight conditions. Apo-CaM and Ca2+ -CaM bind to distinct but overlapping sites in an elongated cleft formed by the handle, helical and central domains. The shift in CaM-binding sites on RyR2 is controlled by Ca2+ binding to CaM, rather than to RyR2. Ca2+ -CaM induces rotations and intradomain shifts of individual central domains, resulting in pore closure of the PCB95 and Ca2+ -activated channel. By contrast, the pore of the ATP, caffeine and Ca2+ -activated channel remains open in the presence of Ca2+ -CaM, which suggests that Ca2+ -CaM is one of the many competing modulators of RyR2 gating.- Published
- 2019
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6. Structure of the human LAT1-4F2hc heteromeric amino acid transporter complex.
- Author
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Yan R, Zhao X, Lei J, and Zhou Q
- Subjects
- Amino Acids metabolism, Binding Sites, Biological Transport, Carboxylic Acids chemistry, Carboxylic Acids pharmacology, Disulfides chemistry, Disulfides metabolism, Fusion Regulatory Protein 1, Heavy Chain antagonists & inhibitors, Fusion Regulatory Protein 1, Heavy Chain metabolism, Humans, Large Neutral Amino Acid-Transporter 1 genetics, Large Neutral Amino Acid-Transporter 1 metabolism, Models, Molecular, Multiprotein Complexes antagonists & inhibitors, Multiprotein Complexes chemistry, Multiprotein Complexes metabolism, Multiprotein Complexes ultrastructure, Norbornanes chemistry, Norbornanes pharmacology, Protein Binding, Protein Conformation, Cryoelectron Microscopy, Fusion Regulatory Protein 1, Heavy Chain chemistry, Fusion Regulatory Protein 1, Heavy Chain ultrastructure, Large Neutral Amino Acid-Transporter 1 chemistry, Large Neutral Amino Acid-Transporter 1 ultrastructure
- Abstract
The L-type amino acid transporter 1 (LAT1; also known as SLC7A5) catalyses the cross-membrane flux of large neutral amino acids in a sodium- and pH-independent manner
1-3 . LAT1, an antiporter of the amino acid-polyamine-organocation superfamily, also catalyses the permeation of thyroid hormones, pharmaceutical drugs, and hormone precursors such as L-3,4-dihydroxyphenylalanine across membranes2-6 . Overexpression of LAT1 has been observed in a wide range of tumour cells, and it is thus a potential target for anti-cancer drugs7-11 . LAT1 forms a heteromeric amino acid transporter complex with 4F2 cell-surface antigen heavy chain (4F2hc; also known as SLC3A2)-a type II membrane glycoprotein that is essential for the stability of LAT1 and for its localization to the plasma membrane8,9 . Despite extensive cell-based characterization of the LAT1-4F2hc complex and structural determination of its homologues in bacteria, the interactions between LAT1 and 4F2hc and the working mechanism of the complex remain largely unknown12-19 . Here we report the cryo-electron microscopy structures of human LAT1-4F2hc alone and in complex with the inhibitor 2-amino-2-norbornanecarboxylic acid at resolutions of 3.3 Å and 3.5 Å, respectively. LAT1 exhibits an inward open conformation. Besides a disulfide bond association, LAT1 also interacts extensively with 4F2hc on the extracellular side, within the membrane, and on the intracellular side. Biochemical analysis reveals that 4F2hc is essential for the transport activity of the complex. Together, our characterizations shed light on the architecture of the LAT1-4F2hc complex, and provide insights into its function and the mechanisms through which it might be associated with disease.- Published
- 2019
- Full Text
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7. Structural basis of Notch recognition by human γ-secretase.
- Author
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Yang G, Zhou R, Zhou Q, Guo X, Yan C, Ke M, Lei J, and Shi Y
- Subjects
- Amino Acid Sequence, Amyloid Precursor Protein Secretases chemistry, Amyloid beta-Protein Precursor chemistry, Amyloid beta-Protein Precursor metabolism, Animals, Humans, Mice, Models, Molecular, Protein Binding, Receptors, Notch chemistry, Substrate Specificity, Amyloid Precursor Protein Secretases metabolism, Amyloid Precursor Protein Secretases ultrastructure, Cryoelectron Microscopy, Receptors, Notch metabolism, Receptors, Notch ultrastructure
- Abstract
Aberrant cleavage of Notch by γ-secretase leads to several types of cancer, but how γ-secretase recognizes its substrate remains unknown. Here we report the cryo-electron microscopy structure of human γ-secretase in complex with a Notch fragment at a resolution of 2.7 Å. The transmembrane helix of Notch is surrounded by three transmembrane domains of PS1, and the carboxyl-terminal β-strand of the Notch fragment forms a β-sheet with two substrate-induced β-strands of PS1 on the intracellular side. Formation of the hybrid β-sheet is essential for substrate cleavage, which occurs at the carboxyl-terminal end of the Notch transmembrane helix. PS1 undergoes pronounced conformational rearrangement upon substrate binding. These features reveal the structural basis of Notch recognition and have implications for the recruitment of the amyloid precursor protein by γ-secretase.
- Published
- 2019
- Full Text
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8. Mechanistic insights into the alternative translation termination by ArfA and RF2.
- Author
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Ma C, Kurita D, Li N, Chen Y, Himeno H, and Gao N
- Subjects
- Codon, Terminator, Escherichia coli chemistry, Escherichia coli genetics, Escherichia coli ultrastructure, Escherichia coli Proteins chemistry, Escherichia coli Proteins ultrastructure, Models, Molecular, Peptide Termination Factors chemistry, Peptide Termination Factors ultrastructure, Protein Binding, Protein Conformation, RNA, Messenger chemistry, RNA-Binding Proteins chemistry, RNA-Binding Proteins ultrastructure, Ribosome Subunits, Small, Bacterial chemistry, Ribosome Subunits, Small, Bacterial metabolism, Ribosome Subunits, Small, Bacterial ultrastructure, Ribosomes chemistry, Ribosomes ultrastructure, Cryoelectron Microscopy, Escherichia coli Proteins metabolism, Peptide Chain Termination, Translational, Peptide Termination Factors metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, RNA-Binding Proteins metabolism, Ribosomes metabolism
- Abstract
During cellular translation of messenger RNAs by ribosomes, the translation apparatus sometimes pauses or stalls at the elongation and termination steps. With the exception of programmed stalling, which is usually used by cells for regulatory purposes, ribosomes stalled on mRNAs need to be terminated and recycled to maintain adequate translation capacity. Much ribosome stalling originates in aberrant mRNAs that lack a stop codon. Transcriptional errors, misprocessing of primary transcripts, and undesired mRNA cleavage all contribute to the formation of non-stop mRNAs. Ribosomes stalled at the 3' end of non-stop mRNAs do not undergo normal termination owing to the lack of specific stop-codon recognition by canonical peptide release factors at the A-site decoding centre. In bacteria, the transfer-messenger RNA (tmRNA)-SmpB-mediated trans-translation rescue system reroutes stalled ribosomes to the normal elongation cycle and translation termination. Two additional rescue systems, ArfA-RF2 (refs 13, 14, 15, 16) and ArfB (formerly known as YaeJ), are also present in many bacterial species, but their mechanisms are not fully understood. Here, using cryo-electron microscopy, we characterize the structure of the Escherichia coli 70S ribosome bound with ArfA, the release factor RF2, a short non-stop mRNA and a cognate P-site tRNA. The C-terminal loop of ArfA occupies the mRNA entry channel on the 30S subunit, whereas its N terminus is sandwiched between the decoding centre and the switch loop of RF2, leading to marked conformational changes in both the decoding centre and RF2. Despite the distinct conformation of RF2, its conserved catalytic GGQ motif is precisely positioned next to the CCA-end of the P-site tRNA. These data illustrate a stop-codon surrogate mechanism for ArfA in facilitating the termination of non-stop ribosomal complexes by RF2.
- Published
- 2017
- Full Text
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9. Diverse roles of assembly factors revealed by structures of late nuclear pre-60S ribosomes.
- Author
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Wu S, Tutuncuoglu B, Yan K, Brown H, Zhang Y, Tan D, Gamalinda M, Yuan Y, Li Z, Jakovljevic J, Ma C, Lei J, Dong MQ, Woolford JL Jr, and Gao N
- Subjects
- Active Transport, Cell Nucleus, Base Sequence, Catalytic Domain, Cell Nucleus chemistry, Cell Nucleus metabolism, Cell Nucleus ultrastructure, Cytoplasm metabolism, DNA, Ribosomal Spacer chemistry, DNA, Ribosomal Spacer genetics, DNA, Ribosomal Spacer metabolism, DNA, Ribosomal Spacer ultrastructure, GTP Phosphohydrolases chemistry, GTP Phosphohydrolases metabolism, GTP Phosphohydrolases ultrastructure, GTP-Binding Proteins chemistry, GTP-Binding Proteins metabolism, GTP-Binding Proteins ultrastructure, Models, Molecular, Molecular Sequence Data, Nuclear Proteins chemistry, Nuclear Proteins metabolism, Nuclear Proteins ultrastructure, Protein Binding, RNA, Fungal genetics, RNA, Fungal metabolism, RNA, Fungal ultrastructure, RNA, Ribosomal genetics, RNA, Ribosomal metabolism, RNA, Ribosomal ultrastructure, Ribonucleoproteins chemistry, Ribonucleoproteins metabolism, Ribonucleoproteins ultrastructure, Ribosomal Proteins chemistry, Ribosomal Proteins isolation & purification, Ribosome Subunits, Large, Eukaryotic metabolism, Rotation, Saccharomyces cerevisiae cytology, Saccharomyces cerevisiae metabolism, Saccharomyces cerevisiae Proteins chemistry, Saccharomyces cerevisiae Proteins isolation & purification, Saccharomyces cerevisiae Proteins metabolism, Saccharomyces cerevisiae Proteins ultrastructure, Cryoelectron Microscopy, Ribosomal Proteins metabolism, Ribosomal Proteins ultrastructure, Ribosome Subunits, Large, Eukaryotic chemistry, Ribosome Subunits, Large, Eukaryotic ultrastructure, Saccharomyces cerevisiae chemistry, Saccharomyces cerevisiae ultrastructure
- Abstract
Ribosome biogenesis is a highly complex process in eukaryotes, involving temporally and spatially regulated ribosomal protein (r-protein) binding and ribosomal RNA remodelling events in the nucleolus, nucleoplasm and cytoplasm. Hundreds of assembly factors, organized into sequential functional groups, facilitate and guide the maturation process into productive assembly branches in and across different cellular compartments. However, the precise mechanisms by which these assembly factors function are largely unknown. Here we use cryo-electron microscopy to characterize the structures of yeast nucleoplasmic pre-60S particles affinity-purified using the epitope-tagged assembly factor Nog2. Our data pinpoint the locations and determine the structures of over 20 assembly factors, which are enriched in two areas: an arc region extending from the central protuberance to the polypeptide tunnel exit, and the domain including the internal transcribed spacer 2 (ITS2) that separates 5.8S and 25S ribosomal RNAs. In particular, two regulatory GTPases, Nog2 and Nog1, act as hub proteins to interact with multiple, distant assembly factors and functional ribosomal RNA elements, manifesting their critical roles in structural remodelling checkpoints and nuclear export. Moreover, our snapshots of compositionally and structurally different pre-60S intermediates provide essential mechanistic details for three major remodelling events before nuclear export: rotation of the 5S ribonucleoprotein, construction of the active centre and ITS2 removal. The rich structural information in our structures provides a framework to dissect molecular roles of diverse assembly factors in eukaryotic ribosome assembly., Competing Interests: The authors declare no competing financial interests.
- Published
- 2016
- Full Text
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10. The crystal structure of Cpf1 in complex with CRISPR RNA.
- Author
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Dong D, Ren K, Qiu X, Zheng J, Guo M, Guan X, Liu H, Li N, Zhang B, Yang D, Ma C, Wang S, Wu D, Ma Y, Fan S, Wang J, Gao N, and Huang Z
- Subjects
- CRISPR-Cas Systems, Crystallography, X-Ray, Genetic Engineering, Models, Molecular, Nucleic Acid Conformation, Protein Binding, Protein Structure, Tertiary, RNA Stability, RNA, Bacterial genetics, RNA, Guide, CRISPR-Cas Systems chemistry, RNA, Guide, CRISPR-Cas Systems genetics, RNA, Guide, CRISPR-Cas Systems metabolism, Substrate Specificity, Bacterial Proteins chemistry, Bacterial Proteins metabolism, CRISPR-Associated Proteins chemistry, CRISPR-Associated Proteins metabolism, Clustered Regularly Interspaced Short Palindromic Repeats genetics, Firmicutes enzymology, RNA, Bacterial chemistry, RNA, Bacterial metabolism
- Abstract
The CRISPR-Cas systems, as exemplified by CRISPR-Cas9, are RNA-guided adaptive immune systems used by bacteria and archaea to defend against viral infection. The CRISPR-Cpf1 system, a new class 2 CRISPR-Cas system, mediates robust DNA interference in human cells. Although functionally conserved, Cpf1 and Cas9 differ in many aspects including their guide RNAs and substrate specificity. Here we report the 2.38 Å crystal structure of the CRISPR RNA (crRNA)-bound Lachnospiraceae bacterium ND2006 Cpf1 (LbCpf1). LbCpf1 has a triangle-shaped architecture with a large positively charged channel at the centre. Recognized by the oligonucleotide-binding domain of LbCpf1, the crRNA adopts a highly distorted conformation stabilized by extensive intramolecular interactions and the (Mg(H2O)6)(2+) ion. The oligonucleotide-binding domain also harbours a looped-out helical domain that is important for LbCpf1 substrate binding. Binding of crRNA or crRNA lacking the guide sequence induces marked conformational changes but no oligomerization of LbCpf1. Our study reveals the crRNA recognition mechanism and provides insight into crRNA-guided substrate binding of LbCpf1, establishing a framework for engineering LbCpf1 to improve its efficiency and specificity for genome editing.
- Published
- 2016
- Full Text
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11. Architecture of the mammalian mechanosensitive Piezo1 channel.
- Author
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Ge J, Li W, Zhao Q, Li N, Chen M, Zhi P, Li R, Gao N, Xiao B, and Yang M
- Subjects
- Animals, Cell Membrane metabolism, Electric Conductivity, Ion Channel Gating, Ion Channels metabolism, Mice, Models, Molecular, Pliability, Protein Multimerization, Protein Structure, Quaternary, Protein Structure, Tertiary, Protein Subunits chemistry, Protein Subunits metabolism, Cryoelectron Microscopy, Ion Channels chemistry, Ion Channels ultrastructure
- Abstract
Piezo proteins are evolutionarily conserved and functionally diverse mechanosensitive cation channels. However, the overall structural architecture and gating mechanisms of Piezo channels have remained unknown. Here we determine the cryo-electron microscopy structure of the full-length (2,547 amino acids) mouse Piezo1 (Piezo1) at a resolution of 4.8 Å. Piezo1 forms a trimeric propeller-like structure (about 900 kilodalton), with the extracellular domains resembling three distal blades and a central cap. The transmembrane region has 14 apparently resolved segments per subunit. These segments form three peripheral wings and a central pore module that encloses a potential ion-conducting pore. The rather flexible extracellular blade domains are connected to the central intracellular domain by three long beam-like structures. This trimeric architecture suggests that Piezo1 may use its peripheral regions as force sensors to gate the central ion-conducting pore.
- Published
- 2015
- Full Text
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12. Structure of the eukaryotic MCM complex at 3.8 Å.
- Author
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Li N, Zhai Y, Zhang Y, Li W, Yang M, Lei J, Tye BK, and Gao N
- Subjects
- Binding Sites, Cell Cycle Proteins chemistry, Cell Cycle Proteins metabolism, Cell Cycle Proteins ultrastructure, Chromatin chemistry, Conserved Sequence, DNA chemistry, DNA metabolism, DNA ultrastructure, DNA-Directed DNA Polymerase chemistry, DNA-Directed DNA Polymerase ultrastructure, G1 Phase, Minichromosome Maintenance Proteins metabolism, Models, Biological, Models, Molecular, Multienzyme Complexes chemistry, Multienzyme Complexes ultrastructure, Nucleic Acid Denaturation, Protein Binding, Protein Multimerization, Protein Structure, Tertiary, Protein Subunits metabolism, Replication Origin, Saccharomyces cerevisiae Proteins chemistry, Saccharomyces cerevisiae Proteins metabolism, Saccharomyces cerevisiae Proteins ultrastructure, Cryoelectron Microscopy, Minichromosome Maintenance Proteins chemistry, Minichromosome Maintenance Proteins ultrastructure, Protein Subunits chemistry, Saccharomyces cerevisiae chemistry, Saccharomyces cerevisiae ultrastructure
- Abstract
DNA replication in eukaryotes is strictly regulated by several mechanisms. A central step in this replication is the assembly of the heterohexameric minichromosome maintenance (MCM2-7) helicase complex at replication origins during G1 phase as an inactive double hexamer. Here, using cryo-electron microscopy, we report a near-atomic structure of the MCM2-7 double hexamer purified from yeast G1 chromatin. Our structure shows that two single hexamers, arranged in a tilted and twisted fashion through interdigitated amino-terminal domain interactions, form a kinked central channel. Four constricted rings consisting of conserved interior β-hairpins from the two single hexamers create a narrow passageway that tightly fits duplex DNA. This narrow passageway, reinforced by the offset of the two single hexamers at the double hexamer interface, is flanked by two pairs of gate-forming subunits, MCM2 and MCM5. These unusual features of the twisted and tilted single hexamers suggest a concerted mechanism for the melting of origin DNA that requires structural deformation of the intervening DNA.
- Published
- 2015
- Full Text
- View/download PDF
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