Full-length model of the human galectin-4 and insights into dynamics of inter-domain communication

Sci Rep. 2016 Sep 19:6:33633. doi: 10.1038/srep33633.

Abstract

Galectins are proteins involved in diverse cellular contexts due to their capacity to decipher and respond to the information encoded by β-galactoside sugars. In particular, human galectin-4, normally expressed in the healthy gastrointestinal tract, displays differential expression in cancerous tissues and is considered a potential drug target for liver and lung cancer. Galectin-4 is a tandem-repeat galectin characterized by two carbohydrate recognition domains connected by a linker-peptide. Despite their relevance to cell function and pathogenesis, structural characterization of full-length tandem-repeat galectins has remained elusive. Here, we investigate galectin-4 using X-ray crystallography, small- and wide-angle X-ray scattering, molecular modelling, molecular dynamics simulations, and differential scanning fluorimetry assays and describe for the first time a structural model for human galectin-4. Our results provide insight into the structural role of the linker-peptide and shed light on the dynamic characteristics of the mechanism of carbohydrate recognition among tandem-repeat galectins.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Crystallography, X-Ray
  • Galectin 4 / chemistry*
  • Galectin 4 / genetics
  • Galectin 4 / metabolism*
  • Humans
  • Models, Molecular*
  • Molecular Dynamics Simulation
  • Protein Conformation
  • Protein Interaction Domains and Motifs*
  • Protein Stability
  • Solubility
  • Structure-Activity Relationship
  • Thermodynamics

Substances

  • Galectin 4