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3swh is a 2 chain structure with sequence from Rattus norvegicus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Unc13/Munc13s play a crucial function in neurotransmitter release through their MUN domain, which mediates the transition from the Syntaxin-1/Munc18-1 complex to the SNARE complex. The MUN domain was suggested to be related to tethering factors, but no MUN-domain structure is available to experimentally validate this notion and address key unresolved questions about the interactions and minimal structural unit required for Unc13/Munc13 function. Here we identify an autonomously folded module within the MUN domain (MUN-CD) and show that its crystal structure is remarkably similar to several tethering factors. We also show that the activity in promoting the Syntaxin-1/Munc18-1 to SNARE complex transition is strongly impaired in MUN-CD. These results show that MUN domains and tethering factors indeed belong to the same family and may have a common role in membrane trafficking. We propose a model whereby the MUN-CD module is central for Munc13 function but full activity requires adjacent sequences.
The Crystal Structure of a Munc13 C-terminal Module Exhibits a Remarkable Similarity to Vesicle Tethering Factors.,Li W, Ma C, Guan R, Xu Y, Tomchick DR, Rizo J Structure. 2011 Oct 12;19(10):1443-55. PMID:22000513[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Li W, Ma C, Guan R, Xu Y, Tomchick DR, Rizo J. The Crystal Structure of a Munc13 C-terminal Module Exhibits a Remarkable Similarity to Vesicle Tethering Factors. Structure. 2011 Oct 12;19(10):1443-55. PMID:22000513 doi:10.1016/j.str.2011.07.012
