9BA4
Full-length cross-linked Contactin 2 (CNTN2)
Summary for 9BA4
Entry DOI | 10.2210/pdb9ba4/pdb |
EMDB information | 44395 |
Descriptor | Contactin-2, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, 2-acetamido-2-deoxy-beta-D-glucopyranose (3 entities in total) |
Functional Keywords | contactins, adhesion molecule, protein structure, conformational changes, homodimer, membrane protein |
Biological source | Homo sapiens (human) |
Total number of polymer chains | 2 |
Total formula weight | 220825.80 |
Authors | Liu, J.L.,Fan, S.F.,Ren, G.R.,Rudenko, G.R. (deposition date: 2024-04-03, release date: 2024-07-17, Last modification date: 2024-11-20) |
Primary citation | Fan, S.,Liu, J.,Chofflet, N.,Bailey, A.O.,Russell, W.K.,Zhang, Z.,Takahashi, H.,Ren, G.,Rudenko, G. Molecular mechanism of contactin 2 homophilic interaction. Structure, 32:1652-1666.e8, 2024 Cited by PubMed Abstract: Contactin 2 (CNTN2) is a cell adhesion molecule involved in axon guidance, neuronal migration, and fasciculation. The ectodomains of CNTN1-CNTN6 are composed of six Ig domains (Ig1-Ig6) and four FN domains. Here, we show that CNTN2 forms transient homophilic interactions (K ∼200 nM). Cryo-EM structures of full-length CNTN2 and CNTN2_Ig1-Ig6 reveal a T-shaped homodimer formed by intertwined, parallel monomers. Unexpectedly, the horseshoe-shaped Ig1-Ig4 headpieces extend their Ig2-Ig3 tips outwards on either side of the homodimer, while Ig4, Ig5, Ig6, and the FN domains form a central stalk. Cross-linking mass spectrometry and cell-based binding assays confirm the 3D assembly of the CNTN2 homodimer. The interface mediating homodimer formation differs between CNTNs, as do the homophilic versus heterophilic interaction mechanisms. The CNTN family thus encodes a versatile molecular platform that supports a very diverse portfolio of protein interactions and that can be leveraged to strategically guide neural circuit development. PubMed: 38968938DOI: 10.1016/j.str.2024.06.004 PDB entries with the same primary citation |
Experimental method | ELECTRON MICROSCOPY (3.54 Å) |
Structure validation
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