Natural cytotoxicity triggering receptor 1(NCR1) is a single-pass type I membrane protein .It contains 2 Ig-like (immunoglobulin-like) domains and belongs to the natural cytotoxicity receptor (NCR) family. The protein is a natural killer (NK) lymphocyte-activating receptor. It is involved in major aspects of NK immune function and shows a high degree of lineage specificity in blood and bone marrow.