Genomic DNA encoding LRIG1 spans a region of 122.89 kilobases on chromosome 3, at 3p14. LRIG1 gene is encoded on the reverse strand.

The pre-mRNA comprises 19 exons.
Coding sequence: 4812 bp.

LRIG1 is a transmembrane cell-surface protein consisting of 1093 amino acids. LRIG1 contains extracellular part containing 15 leucine-rich repeats (LRR) and three C2-type immunoglobulin-like domains, a transmembrane region, and a cytoplasmic tail. LRIG1 can be cut into soluble LRIG1 ectodomain by proteolytic processing, which also is a functional molecule.

LRIG1 is expressed ubiquitously in various epithelial cells, endothelial cells, heart, smooth and striated muscles, and in large neurons.

Differential subcellular distribution in a cell type-specific manner.

LRIG1 acts as a suppressor of receptor tyrosine kinases, such as epidermal growth factor receptor (EGFR) family, MET (hepatocyte growth factor receptor), and RET. The interaction of the extracellular LRR domain and immunoglobulin-like domains of LRIG1 with the extracellular parts of the human EGFR results in recruitment of c-Cbl to the cytoplasmic domains, and induction of EGFR degradation. LRIG1 is involved in signal transduction, cell proliferation, cell apopotosis, cell cycle, cell migration, and cell invasion. LRIG1 as a putative tumor suppressor gene often be down-regulated in various human tumors.
Soluble ectodomain of LRIG1 protein can modulate EGFR signaling and its growth-promoting activity in a paracrine fashion.