eipr-1 Antibody

Definition and Function of EIPR-1 Antibody

The EIPR-1 antibody detects the EIPR1 protein (also known as TSSC1), which interacts with the Endosome-associated recycling protein (EARP) and Golgi-associated retrograde protein (GARP) complexes. These complexes mediate retrograde trafficking from endosomes to the trans-Golgi network (TGN) and plasma membrane . EIPR1 is essential for:

• Stabilizing EARP complex subunits

• Retaining mature DCV cargos (e.g., insulin, neuropeptides) in secretory vesicles

• Regulating insulin secretion in endocrine cells

Applications of EIPR-1 Antibodies in Research

Validated applications include:

Top Validated EIPR-1 Antibodies

Commercial antibodies with peer-reviewed validation:

Role in DCV Cargo Retention

• Loss of EIPR1 in insulinoma cells leads to:

  • 60% reduction in insulin secretion

  • Accumulation of mature cargos (e.g., carboxypeptidase E) near the TGN

  • Reduced DCV cargo retention in cell periphery

Interaction with Trafficking Complexes

• EIPR1 co-immunoprecipitates with VPS51 (EARP) and VPS50 (GARP/EARP) in rat insulinoma cells .

• CRISPR-mediated Eipr1 knockout destabilizes EARP subunits but not GARP .

Evolutionary Conservation

• C. elegans EIPR-1 mutants show defective DCV cargo sorting, phenocopying rab-2 pathway mutants .

• WD40 domain of EIPR1 is critical for scaffolding EARP/GARP complexes across species .

Technical Considerations for EIPR-1 Antibodies

• Validation: KO/WT lysate comparisons are essential (e.g., loss of 45 kDa band in Eipr1 KO cells) .

• Cross-Reactivity: Most antibodies target human EIPR1, but some (e.g., Invitrogen PA5-22360) cross-react with rat .

• Localization: Antibodies should show punctate cytoplasmic staining overlapping with TGN38 or EARP markers .

Future Directions

Current studies focus on:

• EIPR1’s role in neuroendocrine tumors

• High-resolution mapping of EIPR1-EARP interaction sites

• Therapeutic targeting of EIPR1 in diabetes and secretory disorders