Metallophosphoesterase domain-containing protein 1 (MPPED1)

Metallophosphoesterase domain-containing protein 1 (MPPED1) is a highly conserved enzyme predicted to possess metallophosphoesterase activity, hydrolyzing phosphodiester bonds but lacking phosphomonoesterase function[5][3]. It is widely expressed in brain, reproductive, and epithelial tissues. In the male reproductive system, MPPED1 is implicated in regulation of cytoskeletal dynamics during spermiogenesis, particularly in flagella formation and cytoplasm removal, in part through autophagy-dependent degradation of negative cytoskeletal regulators[1]. In neuronal development, MPPED1 participates in cell differentiation and neuronal subtype specification; its expression is highest in brain cortical regions[1][3]. Biochemically, MPPED1 (and its paralog MPPED2) hydrolyze certain cyclic nucleotides (with 2',3'-cAMP as a preferred substrate), but the full range and in vivo relevance of its substrates remain under investigation[3]. The protein has no monoesterase activity, can bind a range of divalent cations, and is often detected as two bands on immunoblots, likely due to alternative translation sites or proteolysis[3]. Currently, there are no known small molecule drugs or validated ligands directly targeting MPPED1 and it is not considered a classic therapeutic target[5][2][3]. Its paralog, MPPED2, is more closely implicated in human disease, while MPPED1's disease relevance is limited and primarily restricted to genomic studies[5][3].

Other names

C22orf1FAM1A239ABAdult brain protein 239