Figure 7.

Alternative splicing of Nix and the function of the isoforms: (A) Alternative splicing of the Nix transcripts gives rise to a longer pre-mRNA with a retained intron. This retained intron contains a premature stop codon and results in a truncated protein product named sNix; and (B) Nix plays a pro-apoptotic role, while sNix plays an anti-apoptotic role by binding to and blocking Nix from interacting with the ER or mitochondrial membranes and inducing calcium release. sNix is also able to block apoptosis by binding to the “NF-κB” transcription factor and altering the genes targeted by the transcription factor [83].