Ectonucleoside Triphosphate Diphosphohydrolase 5 (ENTPD5)

ENTPD5 is similar to E-type nucleotidases (NTPases)/ecto-ATPase/apyrases. NTPases, such as CD39, mediate catabolism of extracellular nucleotides. ENTPD5 contains 4 apyrase-conserved regions which is characteristic of NTPases.The coding regions of the mouse and human CD39L4 genes share 88% nucleotide sequence identity.

The predicted 428-amino acid CD39L4 protein contains all 4 ACRs, a single N-terminal transmembrane segment, and a large extracellular C-terminal domain. Northern blot analysis revealed that CD39L4 was expressed as a 4.8-kb mRNA in all tissues tested. Several smaller bands were also observed in tissues with the strongest CD39L4 expression.