Alpha chain

The term alpha chain is normally used to indicate one of the subunits of a multi-subunit protein. The term "chain" is a general term giving to any peptide sequence. It can often refer more specifically to mean:

• a part of the T-cell receptor,
• the Fibrinogen alpha chain,
• the integrin alpha chain,
• Hemoglobin, alpha 1

It should be distinguished from the term alpha helix, which refers to one of the common secondary structures found in proteins, along with beta sheet.