Human Fc Receptor-Like Protein 1 (FCRL1) Protein

Background

Fc Receptor Like 1 (FCRL1) is a transmembrane protein expressed primarily on B cells and is a member of the immunoglobulin superfamily. It plays a role in regulating B cell activation and immune responses. The cytoplasmic domain of FCRL1 contains both immunoreceptor tyrosine-based activation motifs (ITAMs) and immunoreceptor tyrosine-based inhibitory motifs (ITIMs), suggesting it can transmit both activating and inhibitory signals. Dysregulation of FCRL1 expression has been associated with autoimmune conditions like systemic lupus erythematosus (SLE), indicating its importance in immune tolerance and balance.