Sodium-dependent phosphate transport protein 2B (NaPi-2b) is involved in actively transporting phosphate into cells via Na+ co-transport. NaPi-2b is the main phosphate transport protein in the intestinal brush border membrane, and has a role in the synthesis of surfactant in lungs' alveoli. Defects in NaPi-2b are a cause of pulmonary alveolar microlithiasis, a rare disease characterized by the deposition of calcium phosphate microliths throughout the lungs.The synthetic peptide used to raise the antibody Cat. No. 251343 is selected from a sequence within the N-term region of mouse NaPi-2b. For blocking experiments, a 10 to 100 fold molar excess to antibody is recommended.