Technical Data
NaPi-2B (Npt IIb)
Inorganic phosphate (Pi) levels are hormonally regulated that affects the physiological activity of bone, kidney, and small intestine.A majority of the Pi is absorbed in the small intestine and reabsorbed in the proximal tubules in the kidney. At least 4 groups of structurally and functionally related proteins are in involved in Pi transport: Type I-related NaPi transporters designated NPT1, Npt1, and NaPi-1 respectively in humans, mouse, and rabbit are expressed in the kidney and liver.Its expression and activity are not regulated by Pi deprivation or parathyroid hormone (PTH) and its role in Pi-homeostasis is not clear.Type IIa-related cotransporters, designated NaPi-2 in rat, NaPi-3 or NPT2 in humans, NaPi-4 in opossum, NaPi-5 in flounder vessel, NaPi-6 or Npt-2 in mouse, and NaPi-7 in rabbit, is the primary target for Pi regulation by dietary, hormonal, and tubular Pi reabsorption. Deletion of Npt2 gene produces severe Pi wasting. Type II transporters are expressed in kidney, brain, lung, bone and small intestine.Type IIb, designated as NaPi-IIB or NaPi-2b in rat/mouse, and NaPi-3b in human, is closely related isoform of the NaPi-2 family.It is expressed in small intestine and lung. Type III NaPi transporters, originally described as a family of cell surface receptors for gibbon ape leukemia virus (GALV) and murine amphotropic retrovirus (A-MuLv), share very low (< 20%) sequence homology with Type I and II proteins, and are found in most tissues. The N- and C-termini are predicted to be cytoplasmic.

Suitable for use in ELISA and Western Blot. Other applications not tested.

Recommended Dilutions:
Western Blot: 1-10ug/ml using chemiluminescence. Glycosylated Npt IIb is ~108kD in small intestine.
ELISA: 0.5-1ug/ml
Optimal dilutions to be determined by the researcher

Storage and Stability:
May be stored at 4C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20C. Aliquots are stable for 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
PabIgGAffinity Purified
50ug-20CBlue IceHumanRabbit
Synthetic peptide corresponding to 16aa within the cytoplasmic domain from the N-terminus of human NaPi-2B conjugated to KLH. Species Sequence Homology: mouse, 68% and rat, 62%.
Purified by immunoaffinity chromatography.
Supplied as a liquid in PBS, 0.1% BSA.
Recognizes human NaPi-2B. No significant sequence homology is observed with NaPi-2a or other Pi-transporters (Type-I, III, or IV) transporters.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.
1. Larsson T, 2004 Endocrinology, 145: 3087-3094-IHC. 2. Hilfiker, H., et al., PNAS 95: 14,564-14,569 (1998). 3. Hasimoto, M., et al., Am. J. Physiol. 157: 21-27 (2000). 4. Xu, H., et al., Genomics 62: 281-284 (1999). 5. Field, J.A., et al., BBRC 258: 578-582 (1999). 6. Murer, H., et al., Physiolo. Rev. 80: 1373 (2000).