EARP and GARP complex-interacting protein 1

EIPR1 (EARP and GARP complex-interacting protein 1) is a 387-amino-acid protein that functions as a component of endosomal retrieval machinery, regulating protein transport from early endosomes to recycling endosomes or the trans-Golgi network (UniProt: Q53HC9). It mediates recruitment of the GARP complex to the trans-Golgi network and promotes recycling of internalized transferrin receptor to the plasma membrane through interaction with the EARP complex, thereby controlling cargo distribution and secretion pathways.

EIPR1 is required for stability of EARP complex subunits and proper membrane localization. Its functional role in endosomal–Golgi trafficking implicates it in vesicular transport and protein homeostasis within the secretory pathway (UniProt: Q53HC9). No other disease associations are documented in UniProt.

EIPR1 is associated with Alzheimer's disease and shows reduced abundance in post-mortem AD brain tissue compared to age-matched controls (Chaparral AD proteomics; mean log2 fold-change −0.30). This downregulation may reflect compromised endosomal–Golgi recycling and protein trafficking dysfunction in AD pathology.