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Publication Abstract from PubMed

We have expressed and purified three soluble fragments of the human LRIG1-ECD (extracellular domain): the LRIG1-LRR (leucine-rich repeat) domain, the LRIG1-3Ig (immunoglobulin-like) domain, and the LRIG1-LRR-1Ig fragment using baculovirus vectors in insect cells. The two LRIG1 domains crystallised so that we have been able to determine the three-dimensional structures at 2.3A resolution. We developed a three-dimensional structure for the LRIG1-ECD using homology modelling based on the LINGO-1 structure. The LRIG1-LRR domain and the LRIG1-LRR-1Ig fragment are monomers in solution, whereas the LRIG1-3Ig domain appears to be dimeric. We could not detect any binding of the LRIG1 domains or the LRIG1-LRR-1Ig fragment to the EGF receptor (EGFR), either in solution using biosensor analysis or when the EGFR was expressed on the cell surface. The FLAG-tagged LRIG1-LRR-1Ig fragment binds weakly to colon cancer cells regardless of the presence of EGFRs. Similarly, neither the soluble LRIG1-LRR nor the LRIG1-3Ig domains nor the full-length LRIG1 co-expressed in HEK293 cells inhibited ligand-stimulated activation of cell-surface EGFR.

LRIG1 Extracellular Domain: Structure and Function Analysis.,Xu Y, Soo P, Walker F, Zhang HH, Redpath N, Tan CW, Nicola NA, Adams TE, Garrett TP, Zhang JG, Burgess AW J Mol Biol. 2015 Mar 9. pii: S0022-2836(15)00173-4. doi:, 10.1016/j.jmb.2015.03.001. PMID:25765764^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.