Endosomal protein tyrosine phosphatases (PTPs) dephosphorylate the insulin receptor, which cannot rephosphorylate itself as insulin is removed leaving the receptor in its inactive conformation (Bevan et al. 1996; Drake & Posner 1998). The identity of these PTPs is not definitively established, but structural studies and studies of cell lines and gene-knockout mice indicate that PTPRF / LAR (Ahmed & Goldstein 1997) and PTPN1 / PTP1B (Li et al. 2005) are each capable of mediating this reaction.
The dephosphorylated receptor recycles to the plasma membrane.