kidney injury molecule-1 (KIM-1) is a type 1 transmembrane protein that is not detectable in normal kidney tissue but is expressed at high levels in rodent kidneys with dedifferentiated proximal tubule epithelial cells after ischemic or toxic injury.

Sequence analysis predicted that the 359-amino acid type I HAVCR1 glycoprotein, which is 79% identical to the monkey protein, contains a signal sequence; a 109-amino acid cys-rich N-terminal region with only 1 conserved N-glycosylation site; a 163-amino acid TSP-rich region with 3 N-glycosylation sites, 2 of which are conserved; and a 48-amino acid intracellular domain, 12 residues shorter than that of the monkey protein. Northern blot analysis revealed ubiquitous expression of a 4.4-kb HAVCR1 transcript, with highest levels in kidney and testis.