The Bcl-2 protein family comprises anti- and proapoptotic members, i.e. they protect the cell from death or favour it.
In the study, they have demonstrated and characterized the interaction between Mcl-1 and Bok, two important proteins in this family, which, according to Ismael Mingarro, "control the permeabilisation of the mitochondrial outer membrane, a crucial step in modulating the apoptotic processes of cell death".
Our results suggest that the interaction between Mcl-1 and Bok is a good target for developing new drugs to treat several types of cancer such as malignant melanomas or pulmonary adenocarcinomas",
Ismael Mingarro, Professor and Predoctoral Researcher, University Institute of Biotechnology and Biomedicine, UV Gerard Duart
As the article explains, these cancers have elevated levels of expression of the Mcl-1 protein and/or mutations in their transmembrane segment that correlate with a bad prognosis and low response to current treatments.
Professor Mingarro states that the interaction between these two proteins is specific and occurs in the membrane environment through their hydrophobic (transmembrane) regions of the carboxy-terminal ends of both proteins, unlike among most proteins in the Bcl-2 family that interact with the soluble regions of proteins.
Lucendo, E., et al. (2020) Mcl-1 and Bok transmembrane domains: Unexpected players in the modulation of apoptosis. PNAS. doi.org/10.1073/pnas.2008885117.