1PXU

Crystal structure of chicken NtA from a eukaryotic source at 2.2A resolution

Summary for 1PXU

• Entry DOI: 10.2210/pdb1pxu/pdb
• Related: 1jb3 1jc7
• Descriptor: agrin (2 entities in total)
• Functional Keywords: agrin, structural protein
• Biological source: Gallus gallus (chicken)
• Total number of polymer chains: 1
• Total formula weight: 15174.34

Authors

Stetefeld, J. (deposition date: 2003-07-07, release date: 2004-06-29, Last modification date: 2024-11-13)

Primary citation

Mascarenhas, J.B.,Ruegg, M.A.,Sasaki, T.,Eble, J.A.,Engel, J.,Stetefeld, J.
Structure and laminin-binding specificity of the NtA domain expressed in eukaryotic cells.
Matrix Biol., 23:507-513, 2005

PubMed Abstract: Agrin is a key organizer for postsynaptic differentiation at the neuromuscular junction (NMJ). This activity requires the binding of agrin to the synaptic basal lamina via its N-terminal (NtA) domain. It has been suggested that this binding is mediated by conserved amino acids in the gamma 1 chain of laminin. Here, we report the crystal structure of chicken NtA expressed in eukaryotic HEK293 cells. In contrast to the previously published structure [Stetefeld, J., Jenny, M., Schulthess, T., Landwehr, R., Schumacher, B., Frank, S., Ruegg, M.A., Engel, J., Kammerer, R.A., 2001. The laminin-binding domain of agrin is structurally related to N-TIMP-1. Nat. Struct. Biol., 8, 705-709.], which was derived from the NtA domain expressed in E. coli, the new data show that the N-terminal tail region (amino acid residues Asn1-Arg5) is highly structured. Moreover, the disulfide bridge between Cys2 and Cys74 was also present. In addition, we show that the binding of NtA requires the gamma 1 chain of laminin and is not greatly affected by the composition of beta chains. These results confirm a model of the NtA-laminin complex where conserved amino acids in the gamma 1 chain are prerequisite for the binding to agrin and they further emphasize that the source of protein can be critical in structure determination.

PubMed: 15694127
DOI: 10.1016/j.matbio.2004.11.003

Experimental method

X-RAY DIFFRACTION (2.2 Å)