Ectonucleoside Triphosphate Diphosphohydrolase 6 (ENTPD6)

ENTPD6 is similar to E-type nucleotidases (NTPases). NTPases, such as CD39, mediate catabolism of extracellular nucleotides. ENTPD6 contains 4 apyrase-conserved regions which is characteristic of NTPases.The predicted 484-amino acid CD39L2 protein contains all 4 ACRs, a single N-terminal transmembrane segment, and a large extracellular C-terminal domain. Northern blot analysis revealed that CD39L2 was expressed as a major 2.6-kb and minor 4.4-kb mRNA in all tissues tested. Homology searches yielded ESTs likely to represent the mouse cd39l2 gene.Flow cytometric analysis demonstrated expression on the extracellular membrane. Functional analysis showed that, like CD39L4, CD39L2 preferentially hydrolyzes nucleotide diphosphates rather than triphospates.