This family consists of several eukaryotic mitochondrial 28S ribosomal protein S30 (or programmed cell death protein 9 PDCD9) sequences. The exact function of this family is unknown although it is known to be a component of the mitochondrial ribosome and a component in cellular apoptotic signaling pathways [1].

1: A new face on apoptosis: death-associated protein 3 and PDCD9 are mitochondrial ribosomal proteins. Cavdar Koc E, Ranasinghe A, Burkhart W, Blackburn K, Koc H, Moseley A, Spremulli LL; FEBS Lett 2001;492:166-170. PMID:11248257