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Updated: Aug 11, 2026

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes
07:26

Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes

Published on: October 15, 2016

The human erythrocyte membrane contains a novel 12-kDa inositolphosphate-binding protein that is an immunophilin

E B Cunningham1

  • 1Department of Biochemistry and Molecular Biology, University of Medicine and Dentistry, New Jersey Medical School, Newark 07103-2714, USA.

Biochemical and Biophysical Research Communications
|October 4, 1995
PubMed

A 12-kDa inositolphosphate-binding protein has been identified as a component of the human erythrocyte membrane. Its robust peptidylprolyl cis-trans isomerase activity that is strongly inhibited by the immunosuppressant drugs FK506 and rapamycin indicates that it is an immunophilin belonging to the FKBP class. The finding that its peptidylprolyl cis-trans isomerase activity is also strongly inhibited by nanomolar concentrations of the second messengers inositol 1,4,5-trisphosphate (IP3) and inositol 1,3,4,5-tetrakisphosphate (IP4) suggests that IP3 and IP4 could be physiological ligands for this membrane-associated immunophilin.

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