BH1 Domain

**Semantic type:** Amino Acid Sequence

**Definition:** Found in proteins that regulate apoptosis, conserved a-helix BCL-2 Homology (BH1-4) Domains are critical to protein apoptotic function and the protein ability to interact/dimerize with other family members or regulatory proteins. BH1 contains predominantly hydrophobic residues. BCL-2 family proteins dimerize among pro- and anti-apoptotic class family members. BCL-2 homodimerization appears to involve head-to-tail interaction of N-terminal BH4 resides with more distal BH1, BH2, and BH3 regions. BCL-2/BAX heterodimerization appears to involve tail-to-tail interaction of the BCL-2 BH1, BH2, and BH3 regions and the BAX BH3 domain region. BCL-2 may suppress cell death partly by binding to BAX via the BH3 domain preventing BAX homodimer formation. (NCI)

**Synonyms:** - BCL-2 Homology 1 Domain