5L3N image
Deposition Date 2016-05-23
Release Date 2016-08-10
Last Version Date 2024-11-06
Entry Detail
PDB ID:
5L3N
Keywords:
Title:
D11 bound [N29, S39_PQ]-IGF-II
Biological Source:
Source Organism:
Homo sapiens (Taxon ID: 9606)
Host Organism:
Method Details:
Experimental Method:
Conformers Calculated:
100
Conformers Submitted:
20
Selection Criteria:
structures with the lowest energy
Macromolecular Entities
Polymer Type:polypeptide(L)
Molecule:Insulin-like growth factor II
Gene (Uniprot):IGF2
Chain IDs:A
Chain Length:69
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation
Probing Receptor Specificity by Sampling the Conformational Space of the Insulin-like Growth Factor II C-domain.
J.Biol.Chem. 291 21234 21245 (2016)
PMID: 27510031 DOI: 10.1074/jbc.M116.741041

Abstact

Insulin and insulin-like growth factors I and II are closely related protein hormones. Their distinct evolution has resulted in different yet overlapping biological functions with insulin becoming a key regulator of metabolism, whereas insulin-like growth factors (IGF)-I/II are major growth factors. Insulin and IGFs cross-bind with different affinities to closely related insulin receptor isoforms A and B (IR-A and IR-B) and insulin-like growth factor type I receptor (IGF-1R). Identification of structural determinants in IGFs and insulin that trigger their specific signaling pathways is of increasing importance in designing receptor-specific analogs with potential therapeutic applications. Here, we developed a straightforward protocol for production of recombinant IGF-II and prepared six IGF-II analogs with IGF-I-like mutations. All modified molecules exhibit significantly reduced affinity toward IR-A, particularly the analogs with a Pro-Gln insertion in the C-domain. Moreover, one of the analogs has enhanced binding affinity for IGF-1R due to a synergistic effect of the Pro-Gln insertion and S29N point mutation. Consequently, this analog has almost a 10-fold higher IGF-1R/IR-A binding specificity in comparison with native IGF-II. The established IGF-II purification protocol allowed for cost-effective isotope labeling required for a detailed NMR structural characterization of IGF-II analogs that revealed a link between the altered binding behavior of selected analogs and conformational rearrangement of their C-domains.

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Primary Citation of related structures