Conserved Site

Apoptosis regulator, Bcl-2, BH1 motif, conserved site (IPR020717)

Short name: Bcl2_BH1_motif_CS


Active cell suicide (apoptosis) is induced by events such as growth factor withdrawal and toxins. It is controlled by regulators, which have either an inhibitory effect on programmed cell death (anti-apoptotic) or block the protective effect of inhibitors (pro-apoptotic) [PMID: 15335822,PMID: 8557188]. Many viruses have found a way of countering defensive apoptosis by encoding their own anti-apoptosis genes preventing their target-cells from dying too soon.

All proteins belonging to the Bcl-2 family [PMID: 8910675] contain either a BH1, BH2, BH3, or BH4 motif. All anti-apoptotic proteins contain BH1 and BH2 motifs; some of them contain an additional N-terminal BH4 motif (Bcl-2, Bcl-x(L), Bcl-w), which is never seen in pro-apoptotic proteins, except for Bcl-x(S). On the other hand, all pro-apoptotic proteins contain a BH3 motif (except for Bad) necessary for dimerisation with other proteins of Bcl-2 family and crucial for their killing activity; some of them also contain BH1 and BH2 motifs (Bax, Bak). The BH3 motif is also present in some anti-apoptotic protein, such as Bcl-2 or Bcl-x(L).

GO terms

Biological Process

GO:0042981 regulation of apoptotic process

Molecular Function

No terms assigned in this category.

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns