This is a family of conserved proteins which were originally described as death-associated-protein-3 (DAP-3). The proteins carry a P-loop DNA-binding motif, and induce apoptosis . DAP3 has been shown to be a pro-apoptotic factor in the mitochondrial matrix  and to be crucial for mitochondrial biogenesis and so has also been designated as MRP-S29 (mitochondrial ribosomal protein subunit 29).
Ribosomes are the particles that catalyse mRNA-directed protein synthesis in all organisms. The codons of the mRNA are exposed on the ribosome to allow tRNA binding. This leads to the incorporation of amino acids into the growing polypeptide chain in accordance with the genetic information. Incoming amino acid monomers enter the ribosomal A site in the form of aminoacyl-tRNAs complexed with elongation factor Tu (EF-Tu) and GTP. The growing polypeptide chain, situated in the P site as peptidyl-tRNA, is then transferred to aminoacyl-tRNA and the new peptidyl-tRNA, extended by one residue, is translocated to the P site with the aid the elongation factor G (EF-G) and GTP as the deacylated tRNA is released from the ribosome through one or more exit sites [PUBMED:11297922, PUBMED:11290319]. About 2/3 of the mass of the ribosome consists of RNA and 1/3 of protein. The proteins are named in accordance with the subunit of the ribosome which they belong to - the small (S1 to S31) and the large (L1 to L44). Usually they decorate the rRNA cores of the subunits.
Kissil JL, Cohen O, Raveh T, Kimchi A; , EMBO J. 1999;18:353-362.: Structure-function analysis of an evolutionary conserved protein, DAP3, which mediates TNF-alpha- and Fas-induced cell death. PUBMED:9889192 EPMC:9889192 .
Berger T, Brigl M, Herrmann JM, Vielhauer V, Luckow B, Schlondorff D, Kretzler M; , J Cell Sci. 2000;113:3603-3612.: The apoptosis mediator mDAP-3 is a novel member of a conserved family of mitochondrial proteins. PUBMED:11017876 EPMC:11017876.