Classification
The Ig like domains can be classified as IgV, IgC1, IgC2, or IgI.
Most Ig domains are either variable (IgV) or constant (IgC).
- IgV: IgV domains with 9 beta strands are generally longer than IgC domains with 7 beta strands.
- IgC1 and IgC2: Ig domains of some members of the IgSF resemble IgV domains in the amino acid sequence, yet are similar in size to IgC domains. These are called IgC2 domains, while standard IgC domains are called IgC1 domains.
- IgI: Other Ig domains exist that are called intermediate (I) domains.
Read more about this topic: Immunoglobulin Superfamily