Characterization of dystroglycan binding in adhesion of human induced pluripotent stem cells to laminin-511 E8 fragment

Sci Rep. 2019 Sep 10;9(1):13037. doi: 10.1038/s41598-019-49669-x.

Abstract

Human induced pluripotent stem cells (hiPSCs) grow indefinitely in culture and have the potential to regenerate various tissues. In the development of cell culture systems, a fragment of laminin-511 (LM511-E8) was found to improve the proliferation of stem cells. The adhesion of undifferentiated cells to LM511-E8 is mainly mediated through integrin α6β1. However, the involvement of non-integrin receptors remains unknown in stem cell culture using LM511-E8. Here, we show that dystroglycan (DG) is strongly expressed in hiPSCs. The fully glycosylated DG is functionally active for laminin binding, and although it has been suggested that LM511-E8 lacks DG binding sites, the fragment does weakly bind to DG. We further identified the DG binding sequence in LM511-E8, using synthetic peptides, of which, hE8A5-20 (human laminin α5 2688-2699: KTLPQLLAKLSI) derived from the laminin coiled-coil domain, exhibited DG binding affinity and cell adhesion activity. Deletion and mutation studies show that LLAKLSI is the active core sequence of hE8A5-20, and that, K2696 is a critical amino acid for DG binding. We further demonstrated that hiPSCs adhere to hE8A5-20-conjugated chitosan matrices. The amino acid sequence of DG binding peptides would be useful to design substrata for culture system of undifferentiated and differentiated stem cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Biomarkers
  • Cell Adhesion*
  • Cells, Cultured
  • Dystroglycans / metabolism*
  • Extracellular Matrix
  • Fluorescent Antibody Technique
  • Humans
  • Induced Pluripotent Stem Cells / metabolism*
  • Laminin / chemistry
  • Laminin / metabolism*
  • Peptide Fragments / chemistry
  • Peptide Fragments / metabolism*
  • Protein Binding
  • Protein Transport

Substances

  • Biomarkers
  • Laminin
  • Peptide Fragments
  • laminin-511, human
  • Dystroglycans