NBC1, Rat, Control Peptide (NaHCO3 Cotransporter 1, NBC-1A/1B, hkNBC, rkNBC, pNBC, hhNBC, SLC4A4)

Bicarbonate, along with CO2, is the major pH buffer of biological fluids. A great majority of HCO3- reabsorption occurs via trans-cellular coupling of the luminal Na-H+-exchanger 3 and Na+-H+-ATPase with the basolateral Na+-HCO3- cotransporters (NBC). Several related proteins constitute the emerging NBC family (NBC1-3) of membrane cotransporters that are found in a variety of epithelial and non-epithelial tissues, and may be tissue specific. Physiologically, NBC is electrogenic, Na+ and HCO3- dependent, Cl- independent, and inhibited by stilbenes (DIDS and SITS). The NBC family of proteins are 30-35% related to anion exchangers (AE2 and AE3; SLC4A1-SLC4A3) and display the same protein topology: (a) At least 10 TM domains with both the N and C-termini predicted to be intracellular, (b) presence of a large, glycosylated, extracellular loop between TM5 and TM6; and (c) the lysine residues are conserved at predicted DIDS-reactive sites. NBC1 (human, rat, mouse 1035 aa, also called NBC-1A/1B, hkNBC, rkNBC, pNBC, hhNBC, SLC4A4) was initially cloned from human Kidney. NBC1 is 30-35% identical with AEs. It is strongly expressed in the kidney and pancreas. The rat kidney NBC1 (rkNBC1; 1035 aa) is 86% identical to hkNBC1. Pancreatic NBC (pNBC/hhNBC/SLC4A5, human 1079 aa) has a unique n-terminal 85 aa sequence replacing the 41-aa in kNBC. pNBC is also more widely expressed (pancreas, thyroid, heart, and brain). Rat NBC1 sequence is 100% conserved in rat, 85% in human, and 80% in rabbit and frog NBC1/PSLC4A4/kNBC. This region is also shared 100% with mouse pNBC/PSLC4A5. Therefore, antibodies will recognize both the kidney and pancreatic/heart isoforms. No significant sequence homology of NBC1 was found with NBC2 or NBC3. Source: Rat, a 20aa peptide sequence within the cytoplasmic, C-terminus of rat NBC1. Storage and Stability: May be stored at 4 degrees C for short-term only. For long-term storage and to avoid repeated freezing and thawing, aliquot. Freeze at -20 degrees C or colder. Aliquots are stable for at least 6 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.