The complex of p14ARF and C1QBP (p32) changes the mitochondrial membrane potential and facilitates p53-mediated apoptosis (Itahana and Zhang 2008), but the mechanism has not been elucidated.
It has been reported that p14ARF can localize to the mitochondrion independently of C1QBP and trigger p53-independent apoptosis (Irvine et al. 2010).
A short isoform of p14ARF, smARF, which lacks 47 N-terminal amino acids, has been reported to localize exclusively to mitochondria where it binds to C1QBP and promotes autophagy (Reef et al. 2007). However, exclusive mitochondrial localization of smARF was not reproduced by other studies (Itahana, Clegg et al. 2008, Irvine et al. 2010). Several mutations in exon 2 of the CDKN2A gene that affect p14ARF, but not p16INK4A, have been reported to impair p14ARF-mediated autophagy through an unknown mechanism (Budina-Kolomets et al. 2013).