Previously, in our laboratory a 40kDa zinc transporter protein has been purified and functionally reconstituted in proteolipososmes. Further, we report the identification of Slc39a10 cDNA encoding 40kDa zinc transporter protein by isolating a cloned DNA complementary to zinc transporter mRNA. cDNA was constructed from immunoenriched mRNA encoding zinc transporter. cDNA was inserted into pBR322 using poly(dC)- poly(dG) tailing. E.coli DH5 cells were transformed and colonies were screened for zinc transporter cDNA by insertional inactivation. Plasmid DNA was purified from the ampicillin sensitive clones and the cDNA was sequenced from both strands. Blast search of cDNA revealed that it belongs to the Slc39 gene family of zinc transporters and was designated as Slc39a10. Zinc transporter protein deduced on the basis of cDNA sequence was named as rZip10 and consists of 385 amino acids with 9 predicted transmembrane domains. Slc39a10 gene was abundantly expressed in both rat and human tissues. Increased extracellular zinc concentration resulted in up-regulation of Slc39a10 in LLCPK1 cells expressing rZip10 which were down-regulated at higher zinc concentrations. These cells accumulated more zinc than control cells. rZip10-mediated zinc uptake activity was time-, temperature- and concentration-dependent and saturable which followed Michaelis-Menten kinetics with a K_m of 19.2µM and V_max of 50pmol/min/mg protein. This activity was competitively inhibited by cadmium with K_i of 91µM. rZip10- mediated zinc uptake was inhibited by -COOH group modifying agents such as DCC. Immunofluorescence studies showed that rZip10 localizes to the plasma membrane of LLC-PK1 cells.