Interaction of AIM with insulin-like growth factor-binding protein-4

Int J Mol Med. 2015 Sep;36(3):833-8. doi: 10.3892/ijmm.2015.2262. Epub 2015 Jun 26.

Abstract

Apoptosis inhibitor of macrophages (AIM/cluster of differentiation 5 antigen-like/soluble protein α) has been shown to inhibit cellular apoptosis; however, the underlying molecular mechanism has not been elucidated. Using yeast two‑hybrid screening, the present study uncovered that AIM binds to insulin‑like growth factor binding protein‑4 (IGFBP‑4). AIM interaction with IGFBP‑4, as well as IGFBP‑2 and ‑3, but not with IGFBP‑1, ‑5 and ‑6, was further confirmed by co‑immunoprecipitation (co‑IP) using 293 cells. The binding activity and affinity between AIM and IGFBP‑4 in vitro were analyzed by co‑IP and biolayer interferometry. Serum depletion‑induced cellular apoptosis was attenuated by insulin‑like growth factor‑I (IGF‑I), and this effect was abrogated by IGFBP‑4. Of note, in the presence of AIM, the inhibitory effect of IGFBP‑4 on the anti‑apoptosis function of IGF‑I was attenuated, possibly through binding of AIM with IGFBP‑4. In conclusion, to the best of our knowledge, the present study provides the first evidence that AIM binds to IGFBP‑2, ‑3 and ‑4. The data suggest that this interaction may contribute to the mechanism of AIM-mediated anti-apoptosis function.

Publication types

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

MeSH terms

  • Apoptosis
  • Apoptosis Regulatory Proteins
  • Cell Line
  • Humans
  • Immunoprecipitation
  • Insulin-Like Growth Factor Binding Protein 2 / metabolism
  • Insulin-Like Growth Factor Binding Protein 3 / metabolism
  • Insulin-Like Growth Factor Binding Protein 4 / metabolism*
  • Insulin-Like Growth Factor I / metabolism
  • Protein Interaction Maps
  • Receptors, Scavenger
  • Scavenger Receptors, Class B / metabolism*

Substances

  • Apoptosis Regulatory Proteins
  • CD5L protein, human
  • Insulin-Like Growth Factor Binding Protein 2
  • Insulin-Like Growth Factor Binding Protein 3
  • Insulin-Like Growth Factor Binding Protein 4
  • Receptors, Scavenger
  • Scavenger Receptors, Class B
  • Insulin-Like Growth Factor I