LRRN1 is a 95kD member of the neuronal LRR family of proteins. It is a cell-surface glycoprotein that is expressed on embryonic motor neurons and somatic myoblasts. Human LRRN1 is 716aa in length. It is a type I transmembrane protein that contains a 606aa extracellular region aa26-631 and a short 64aa cytoplasmic tail. The extracellular region shows eleven LRRs aa94-384 that mediate protein-protein interactions, one C2-type Ig-like domain and one fibronectin type III domain. There is one potential alternate start site at Met286. Over aa26-631, human LRRN1 shares 96% aa sequence identity with mouse LRRN1.