Leucine Rich Repeats And Immunoglobulin Like Domains Protein 1 (LRIG1)

The deduced 1,093-amino acid protein contains an extracellular N-terminal region with 15 leucine-rich repeats and 3 C2-type immunoglobulin-like domains, followed by a transmembrane region and a cytoplasmic tail.

LRIG1 has 6 potential N-glycosylation sites. Mouse and human LRIG1 share 83% amino acid identity, with highest conservation in the extracellular, transmembrane, and membrane-proximal regions. Northern blot analysis detected an LRIG1 transcript of about 5.5 kb abundantly expressed in brain, heart, kidney, skeletal muscle, stomach, and testis. Quantitative RT-PCR detected expression in all tissues examined, with highest expression in brain. Lowest expression was in spleen, which showed 240-fold lower expression compared with brain.