Immunoglobulin Superfamily Containing Leucine Rich Repeat Protein (ISLR)

Nagasawa et al. (1997) isolated a cDNA for a novel human protein containing both a leucine-rich repeat (LRR) and an immunoglobulin (Ig)-like domain. ISLR was referred to as ISLR for """immunoglobulin superfamily containing LRR.""" The predicted protein comprises 428 amino acids and contains a hydrophobic N-terminal 18-amino acid putative signal peptide. Despite the variety of their functions, all members of the Ig superfamily  are involved in adhesion or binding to other proteins in solution or at the cell surface. Therefore it is possible that the ISLR protein may also interact with other proteins or cells. On Northern blot analysis, the authors found a 2.4-kb ISLR transcript in various human tissues, including retina, heart, skeletal muscle, prostate, ovary, small intestine, thyroid, adrenal cortex, testis, stomach, and spinal cord, as well as fetal lung and fetal kidney.