Therapeutic targeting of insulin-regulated aminopeptidase: heads and tails?

Anthony L Albiston1, Grantley R Peck, Holly R Yeatman

  • 1Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Victoria 3010, Australia.

Pharmacology & Therapeutics
|September 29, 2007
PubMed

Insulin-regulated aminopeptidase, IRAP, is an abundant protein that was initially cloned from a rat epididymal fat pad cDNA library as a marker protein for specialized vesicles containing the insulin-responsive glucose transporter GLUT4, wherein it is thought to participate in the tethering and trafficking of GLUT4 vesicles. The same protein was independently cloned from human placental cDNA library as oxytocinase and is proposed to have a primary role in the regulation of circulating oxytocin (OXY) during the later stages of pregnancy. More recently, IRAP was identified as the specific binding site for angiotensin IV, and we propose that it mediates the memory-enhancing effects of the peptide. This protein appears to have multiple physiological roles that are tissue- and domain-specific; thus the protein can be specifically targeted for treating different clinical conditions.

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