Rapid neurotransmitter release depends on the Ca 2+ sensor Synaptotagmin-1 (Syt1) and the SNARE complex formed by synaptobrevin, syntaxin-1 and SNAP-25. How Syt1 triggers release has been unclear, partly because elucidating high-resolution structures of Syt1-SNARE complexes has been challenging. An NMR approach based on lanthanide-induced pseudocontact shifts now reveals a dynamic binding mode in which basic residues in the concave side of the Syt1 C 2 B-domain β-sandwich interact with a polyacidic region of the SNARE complex formed by syntaxin-1 and SNAP-25. The physiological relevance of this dynamic structural model is supported by mutations in basic residues of Syt1 that markedly impair SNARE-complex binding in vitro and Syt1 function in neurons. Mutations with milder effects on binding have correspondingly milder effects on Syt1 function. Our results support a model whereby dynamic interaction facilitates cooperation between Syt1 and the SNAREs in inducing membrane fusion.

Dynamic binding mode of a Synaptotagmin-1-SNARE complex in solution / K.D. Brewer, T. Bacaj, A. Cavalli, C. Camilloni, J.D. Swarbrick, J. Liu, A. Zhou, P. Zhou, N. Barlow, J. Xu, A.B. Seven, E.A. Prinslow, R. Voleti, D. Häussinger, A.M.J.J. Bonvin, D.R. Tomchick, M. Vendruscolo, B. Graham, T.C. Südhof, J. Rizo. - In: NATURE STRUCTURAL & MOLECULAR BIOLOGY. - ISSN 1545-9993. - 22:7(2015), pp. 555-564. [10.1038/nsmb.3035]

Dynamic binding mode of a Synaptotagmin-1-SNARE complex in solution

C. Camilloni;
2015

Abstract

Rapid neurotransmitter release depends on the Ca 2+ sensor Synaptotagmin-1 (Syt1) and the SNARE complex formed by synaptobrevin, syntaxin-1 and SNAP-25. How Syt1 triggers release has been unclear, partly because elucidating high-resolution structures of Syt1-SNARE complexes has been challenging. An NMR approach based on lanthanide-induced pseudocontact shifts now reveals a dynamic binding mode in which basic residues in the concave side of the Syt1 C 2 B-domain β-sandwich interact with a polyacidic region of the SNARE complex formed by syntaxin-1 and SNAP-25. The physiological relevance of this dynamic structural model is supported by mutations in basic residues of Syt1 that markedly impair SNARE-complex binding in vitro and Syt1 function in neurons. Mutations with milder effects on binding have correspondingly milder effects on Syt1 function. Our results support a model whereby dynamic interaction facilitates cooperation between Syt1 and the SNAREs in inducing membrane fusion.
Animals; Cells, Cultured; Humans; Mice, Inbred C57BL; Models, Molecular; Neurons; Nuclear Magnetic Resonance, Biomolecular; Protein Binding; Protein Structure, Tertiary; Rats; SNARE Proteins; Synaptotagmin I; Structural Biology; Molecular Biology
Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
Settore BIO/10 - Biochimica
2015
https://hdl.handle.net/2434/714966
Article (author)
File in questo prodotto:
File Dimensione Formato  
nsmb.3035.pdf

accesso riservato

Tipologia: Publisher's version/PDF
Dimensione 4.36 MB
Formato Adobe PDF
4.36 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
nihms685377.pdf

accesso aperto

Tipologia: Pre-print (manoscritto inviato all'editore)
Dimensione 2.56 MB
Formato Adobe PDF
2.56 MB Adobe PDF Visualizza/Apri
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/494790
Citazioni
  • ???jsp.display-item.citation.pmc??? 67
  • Scopus 117
  • ???jsp.display-item.citation.isi??? 111
social impact