Focus on Membrane Fusion

Bringing it together - p653

doi:10.1038/nsmb0708-653

An in-depth look at membrane fusion—a process essential for communication within and between cells—is presented in this issue of Nature Structural & Molecular Biology.

Full Text - Bringing it together | PDF (227 KB) - Bringing it together

Focus on Membrane Fusion

Some classic papers in the field of membrane fusion—a personal view - pp655 - 657

Reinhard Jahn

doi:10.1038/nsmb0708-655

Every field of research has influential papers that have shaped and guided future work. Reinhard Jahn gives his picks for membrane fusion and a little bit of history about how the field has developed.

Full Text - Some classic papers in the field of membrane fusion—a personal view | PDF (168 KB) - Some classic papers in the field of membrane fusion—a personal view

Focus on Membrane Fusion

Membrane fusion - pp658 - 664

William Wickner & Randy Schekman

doi:10.1038/nsmb.1451

Abstract - | Full Text - Membrane fusion | PDF (528 KB) - Membrane fusion

Focus on Membrane Fusion

Synaptic vesicle fusion - pp665 - 674

Josep Rizo & Christian Rosenmund

doi:10.1038/nsmb.1450

Abstract - | Full Text - Synaptic vesicle fusion | PDF (851 KB) - Synaptic vesicle fusion

Focus on Membrane Fusion

Mechanics of membrane fusion - pp675 - 683

Leonid V Chernomordik & Michael M Kozlov

doi:10.1038/nsmb.1455

Abstract - | Full Text - Mechanics of membrane fusion | PDF (1,280 KB) - Mechanics of membrane fusion

Focus on Membrane Fusion

The fusion pores of Ca²⁺-triggered exocytosis - pp684 - 689

Meyer B Jackson & Edwin R Chapman

doi:10.1038/nsmb.1449

Abstract - | Full Text - The fusion pores of Ca2+-triggered exocytosis | PDF (1,643 KB) - The fusion pores of Ca2+-triggered exocytosis

Focus on Membrane Fusion

Viral membrane fusion - pp690 - 698

Stephen C Harrison

doi:10.1038/nsmb.1456

Abstract - | Full Text - Viral membrane fusion | PDF (1,042 KB) - Viral membrane fusion

Research highlights - p699

doi:10.1038/nsmb0708-699

Full Text - Research highlights | PDF (134 KB) - Research highlights

Supramolecular SNARE assembly precedes hemifusion in SNARE-mediated membrane fusion - pp700 - 706

Xiaobing Lu, Yinghui Zhang & Yeon-Kyun Shin

doi:10.1038/nsmb.1433

The cooperative action of multiple trans SNARE complexes are a likely requirement for successful membrane fusion. New in vitro analyses reveal the kinetic timescales of the sequential steps of the fusion process, beginning with trans SNARE pairing and clustering of vesicle SNARE proteins, proceeding to hemifusion of outer bilayer leaflets, and ending with full fusion.

Abstract - | Full Text - Supramolecular SNARE assembly precedes hemifusion in SNARE-mediated membrane fusion | PDF (533 KB) - Supramolecular SNARE assembly precedes hemifusion in SNARE-mediated membrane fusion | Supplementary information

Complexin and Ca²⁺ stimulate SNARE-mediated membrane fusion - pp707 - 713

Tae-Young Yoon, Xiaobing Lu, Jiajie Diao, Soo-Min Lee, Taekjip Ha & Yeon-Kyun Shin

doi:10.1038/nsmb.1446

Complexin is one of several regulatory molecules known to be important for SNARE-mediated fusion that occurs during neurotransmitter release. In vitro data now suggest that complexin plays inhibitory and Ca²⁺- dependent stimulatory roles that may be correlated to changing interactions with the SNARE complex.

Abstract - | Full Text - Complexin and Ca2+ stimulate SNARE-mediated membrane fusion | PDF (697 KB) - Complexin and Ca2+ stimulate SNARE-mediated membrane fusion | Supplementary information

Capped small RNAs and MOV10 in human hepatitis delta virus replication - pp714 - 721

Dirk Haussecker, Dan Cao, Yong Huang, Poornima Parameswaran, Andrew Z Fire & Mark A Kay

doi:10.1038/nsmb.1440

Both genomic and antigenomic hepatitis delta virus (HDV) RNAs have hairpin-shaped ends. Small capped RNAs have now been identified from both genomic and antigenomic RNAs, and the human homolog of the Arabidopsis RNA amplification factor (SDE3) has been implicated in the replication of HDV.

Abstract - | Full Text - Capped small RNAs and MOV10 in human hepatitis delta virus replication | PDF (542 KB) - Capped small RNAs and MOV10 in human hepatitis delta virus replication | Supplementary information

Asymmetric bidirectional replication at the human DBF4 origin - pp722 - 729

Julia Romero & Hoyun Lee

doi:10.1038/nsmb.1439

The origin of replication located at the human DBF4 promoter is finely characterized. Two initiation zones are on opposite strands and 400 bp apart, being fired in a sequential way, in a manner similar to replication at bacterial oriC.

Abstract - | Full Text - Asymmetric bidirectional replication at the human DBF4 origin | PDF (591 KB) - Asymmetric bidirectional replication at the human DBF4 origin | Supplementary information

Molecular mechanism of energy conservation in polysulfide respiration - pp730 - 737

Mika Jormakka, Ken Yokoyama, Takahiro Yano, Masatada Tamakoshi, Satoru Akimoto, Tatsuro Shimamura, Paul Curmi & So Iwata

doi:10.1038/nsmb.1434

• PDB code

  • 2VPW
  • 2VPX
  • 2VPY
  • 2VPZ

• 3D view

  • 2VPW
  • 2VPX
  • 2VPY
  • 2VPZ

Polysulfides are chains of sulfur atoms abundant in extreme environments. Some organisms reduce polysulfides, and this reaction may be coupled to respiratory processes. Now the structure of the multicomponent membrane complex that catalyzes this reaction is solved, revealing a potential proton channel that could have a role in energy conservation.

Abstract - | Full Text - Molecular mechanism of energy conservation in polysulfide respiration | PDF (653 KB) - Molecular mechanism of energy conservation in polysulfide respiration | Supplementary information

Fungal Rtt109 histone acetyltransferase is an unexpected structural homolog of metazoan p300/CBP - pp738 - 745

Yong Tang, Marc A Holbert, Hugo Wurtele, Katrina Meeth, Walter Rocha, Marlene Gharib, Eva Jiang, Pierre Thibault, Alain Verreault, Philip A Cole & Ronen Marmorstein

doi:10.1038/nsmb.1448

• PDB code

  • 3D35

• 3D view

  • 3D35

Rtt109 is a relatively recently identified yeast histone acetyltransferase that forms distinct complexes with two histone chaperones. The structure of Rtt109 now reveals that while functionally distinct, it is structurally homologous to mammalian p300/CBP, which previously appeared to not contain a counterpart in yeast.

Abstract - | Full Text - Fungal Rtt109 histone acetyltransferase is an unexpected structural homolog of metazoan p300/CBP | PDF (761 KB) - Fungal Rtt109 histone acetyltransferase is an unexpected structural homolog of metazoan p300/CBP | Supplementary information

Mechanism of lid closure in the eukaryotic chaperonin TRiC/CCT - pp746 - 753

Christopher R Booth, Anne S Meyer, Yao Cong, Maya Topf, Andrej Sali, Steven J Ludtke, Wah Chiu & Judith Frydman

doi:10.1038/nsmb.1436

Group II chaperonins, such as TriC/CCT, have a build-in lid that can cover the folding chamber and functions in an analogous way to the GroES-like proteins used by their Group I counterparts. Structural and modeling data suggest an allosteric mechanism of TriC lid closure that differs from GroES–GroEL systems.

Abstract - | Full Text - Mechanism of lid closure in the eukaryotic chaperonin TRiC/CCT | PDF (829 KB) - Mechanism of lid closure in the eukaryotic chaperonin TRiC/CCT | Supplementary information

GroEL as a molecular scaffold for structural analysis of the anthrax toxin pore - pp754 - 760

Hiroo Katayama, Blythe E Janowiak, Marek Brzozowski, Jordan Juryck, Scott Falke, Edward P Gogol, R John Collier & Mark T Fisher

doi:10.1038/nsmb.1442

The protective antigen (PA) moiety of anthrax toxin exists as a stable prepore, converting into the pore form under low pH to translocate the enzymatic components across the host cell membrane. The PA pore rapidly aggregates in solution, and it is now shown that the chaperone GroEL can stabilize the PA pore, allowing single-particle EM analysis. This method could be useful for other membrane protein complexes.

Abstract - | Full Text - GroEL as a molecular scaffold for structural analysis of the anthrax toxin pore | PDF (563 KB) - GroEL as a molecular scaffold for structural analysis of the anthrax toxin pore | Supplementary information

A second binding site for double-stranded RNA in TLR3 and consequences for interferon activation - pp761 - 763

Nina Pirher, Karolina Iviak, Jelka Pohar, Mojca Benina & Roman Jerala

doi:10.1038/nsmb.1453

Toll-like receptor 3 (TLR3) recognizes double-stranded RNA (dsRNA) molecules produced by many viruses and activates an inflammatory response. Synthetic dsRNAs such as small interfering RNAs have been shown to activate TLR3. Now the TLR3 ectodomain is found to contain two dsRNA binding sites, and the implications for dsRNA recognition and selectivity and downstream signaling are discussed.

Abstract - | Full Text - A second binding site for double-stranded RNA in TLR3 and consequences for interferon activation | PDF (410 KB) - A second binding site for double-stranded RNA in TLR3 and consequences for interferon activation | Supplementary information

Structure of an O-GlcNAc transferase homolog provides insight into intracellular glycosylation - pp764 - 765

Carlos Martinez-Fleites, Matthew S Macauley, Yuan He, David L Shen, David J Vocadlo & Gideon J Davies

doi:10.1038/nsmb.1443

• PDB code

  • 2VSN

• 3D view

  • 2VSN

Cytoplasmic O-GlcNac modification of proteins is thought to have dynamic interplay with phosphorylation and thus be involved in regulation of signaling processes. The complete structure of an OGT homolog is now presented, suggesting how diverse ligands can be presented to the active site of the enzyme.

Abstract - | Full Text - Structure of an O-GlcNAc transferase homolog provides insight into intracellular glycosylation | PDF (277 KB) - Structure of an O-GlcNAc transferase homolog provides insight into intracellular glycosylation | Supplementary information