DPH2 (diphthamide biosynthesis protein 2), also known as DPH2L2, is a 489 amino acid protein that shows strong expression in skeletal muscle; moderate expression in heart, small intestine, liver, pancreas, testis and colon; and lesser expression in brain, placenta, kidney, spleen, thymus, prostate, ovary and lymphocytes. DPH2 interacts with DPH1 and, functioning together as a dimer or multimer, DPH1 and DPH2 may participate in diphthamide biosynthesis. Diphthamide is a posttranslationally modified histidine residue which occurs in EF-2 (elongation factor 2) and targets diphtheria toxin ADP-ribosylation. The loss of DPH2 in Saccharomyces cerevisiae is believed to suppress zymocicity. Two transcript variants encoding different isoforms have been found for this gene.

Required for the first step in the synthesis of diphthamide, a post-translational modification of histidine which occurs in translation elongation factor 2.

Tissue specificity:
Strongly expressed in skeletal muscle. Moderately expressed in heart, small intestine, liver, pancreas, testis and colon. Weakly expressed in brain, placenta, kidney, speen, thymus, prostate, ovary and lymphocytes.