Acts as a feedback negative regulator of signaling by receptor tyrosine kinases, through a mechanism that involves enhancement of receptor ubiquitination and accelerated intracellular degradation. Interacts (via extracellular LRR and Ig-like domains) with EGFR/ERBB1, ERBB2, ERBB3 and ERBB4 (via extracellular domain) (PubMed:15282549). The physiological relevance of the interaction is controversial; LRIG1 may have low affinity for EGFR, and interaction may occur only when high levels of both proteins are present (PubMed:25765764). Widely expressed. By EGF. Contains LRR and Ig-domains that can mediate low-affinity interaction with EGFR (PubMed:25765764). The LRRs and the Ig-domains are each sufficient for EGFR/ERBB1 binding. This interaction is abolished only when both the LRRs and the Ig-domains are deleted (PubMed:15282549).