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-Structure paper
Title | Allosteric activation of preformed EGF receptor dimers by a single ligand binding event. |
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Journal, issue, pages | Front Endocrinol (Lausanne), Vol. 13, Page 1042787, Year 2022 |
Publish date | Nov 30, 2022 |
Authors | Endang R Purba / Ei-Ichiro Saita / Reetesh R Akhouri / Lars-Goran Öfverstedt / Gunnar Wilken / Ulf Skoglund / Ichiro N Maruyama / |
PubMed Abstract | Aberrant activation of the epidermal growth factor receptor (EGFR) by mutations has been implicated in a variety of human cancers. Elucidation of the structure of the full-length receptor is ...Aberrant activation of the epidermal growth factor receptor (EGFR) by mutations has been implicated in a variety of human cancers. Elucidation of the structure of the full-length receptor is essential to understand the molecular mechanisms underlying its activation. Unlike previously anticipated, here, we report that purified full-length EGFR adopts a homodimeric form before and after ligand binding. Cryo-electron tomography analysis of the purified receptor also showed that the extracellular domains of the receptor dimer, which are conformationally flexible before activation, are stabilized by ligand binding. This conformational flexibility stabilization most likely accompanies rotation of the entire extracellular domain and the transmembrane domain, resulting in dissociation of the intracellular kinase dimer and, thus, rearranging it into an active form. Consistently, mutations of amino acid residues at the interface of the symmetric inactive kinase dimer spontaneously activate the receptor . Optical observation also indicated that binding of only one ligand activates the receptor dimer on the cell surface. Our results suggest how oncogenic mutations spontaneously activate the receptor and shed light on the development of novel cancer therapies. |
External links | Front Endocrinol (Lausanne) / PubMed:36531494 / PubMed Central |
Methods | EM (tomography) |
Resolution | 15.0 Å |
Structure data | EMDB-30862: EMDB-30864: |
Source |
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