Immunoglobulin Domains

**Definition:** Compact globular protein domains of about 80 to 110 amino acids.They are characterized by two antiparallel beta sheets stabilized by HYDROPHOBIC INTERACTIONS and disulfide bonds between opposing strands. Three major subtypes of Ig domains are recognized: variable (V), intermediate (I), and constant (C1 or C2). Members of the immunoglobulin superfamily include ANTIGEN RECEPTORS; CYTOKINE RECEPTORS; and CELL ADHESION MOLECULES which possess immunoglobulin domains.

**Tree numbers:** - G02.111.570.820.709.275.750.250

**Synonyms:** - Ig Fold - Immunoglobulin Domain - Ig Domains - Ig Domain