2KBC

Solution structure of human insulin-like peptide 5 (INSL5)


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of human insulin-like peptide 5 and characterization of conserved hydrogen bonds and electrostatic interactions within the relaxin framework

Hossain, M.A.Daly, N.L.Craik, D.J.Wade, J.D.Rosengren, K.J.

(2009) Biochem.J. 419: 619-627

  • DOI: 10.1042/BJ20082353

  • PubMed Abstract: 
  • INSL5 (insulin-like peptide 5) is a two-chain peptide hormone related to insulin and relaxin. It was recently discovered through searches of expressed sequence tag databases and, although the full biological significance of INSL5 is still being eluci ...

    INSL5 (insulin-like peptide 5) is a two-chain peptide hormone related to insulin and relaxin. It was recently discovered through searches of expressed sequence tag databases and, although the full biological significance of INSL5 is still being elucidated, high expression in peripheral tissues such as the colon, as well as in the brain and hypothalamus, suggests roles in gut contractility and neuroendocrine signalling. INSL5 activates the relaxin family peptide receptor 4 with high potency and appears to be the endogenous ligand for this receptor, on the basis of overlapping expression profiles and their apparent co-evolution. In the present study, we have used solution-state NMR to characterize the three-dimensional structure of synthetic human INSL5. The structure reveals an insulin/relaxin-like fold with three helical segments that are braced by three disulfide bonds and enclose a hydrophobic core. Furthermore, we characterized in detail the hydrogen-bond network and electrostatic interactions between charged groups in INSL5 by NMR-monitored temperature and pH titrations and undertook a comprehensive structural comparison with other members of the relaxin family, thus identifying the conserved structural features of the relaxin fold. The B-chain helix, which is the primary receptor-binding site of the relaxins, is longer in INSL5 than in its close relative relaxin-3. As this feature results in a different positioning of the receptor-activation domain Arg(B23) and Trp(B24), it may be an important contributor to the difference in biological activity observed for these two peptides. Overall, the structural studies provide mechanistic insights into the receptor selectivity of this important family of hormones.


    Organizational Affiliation

    School of Pure and Applied Natural Sciences, University of Kalmar, Kalmar, Sweden.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
INSL5_B-chain
B
25Homo sapiensMutation(s): 0 
Gene Names: INSL5
Find proteins for Q9Y5Q6 (Homo sapiens)
Go to Gene View: INSL5
Go to UniProtKB:  Q9Y5Q6
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
INSL5_A-chain
A
22Homo sapiensMutation(s): 0 
Gene Names: INSL5
Find proteins for Q9Y5Q6 (Homo sapiens)
Go to Gene View: INSL5
Go to UniProtKB:  Q9Y5Q6
Small Molecules
Modified Residues  2 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
A, B
NON-POLYMERH2 N

--

PCA
Query on PCA
A
L-PEPTIDE LINKINGC5 H7 N O3GLU
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2KBC Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-03-24
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2018-02-07
    Type: Derived calculations, Experimental preparation, Source and taxonomy