The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.
Application notesIHC-Fr: Use at an assay dependent dilution. (see refeences below: Schmitt BM et al. Immunolocalization of the electrogenic Na+-HCO-3 cotransporter in mammalian and amphibian kidney. Jensen LJ et al. Localization of sodium bicarbonate cotransporter (NBC) protein and messenger ribonucleic acid in rat epididymis. Marino CR et al. Expression and distribution of the Na(+)-HCO(-)(3) cotransporter in human pancreas. Romero MF et al. Cloning and functional expression of rNBC, an electrogenic Na(+)-HCO3- cotransporter from rat kidney.
Not yet tested in other applications.
Optimal dilutions/concentrations should be determined by the end user.
FunctionElectrogenic sodium/bicarbonate cotransporter with a Na(+):HCO3(-) stoichiometry varying from 1:2 to 1:3. May regulate bicarbonate influx/efflux at the basolateral membrane of cells and regulate intracellular pH.
Tissue specificityIsoform 1 is expressed in pancreas and to a lower extent in heart, skeletal muscle, liver, parotid salivary glands, prostate, colon, stomach, thyroid, brain and spinal chord. Corneal endothelium cells express only isoform 1 (at protein level). Isoform 2 is specifically expressed in kidney at the level of proximal tubules.
Involvement in diseaseDefects in SLC4A4 are the cause of proximal renal tubular acidosis with ocular abnormalities (pRTA-OA) [MIM:604278]; also known as renal tubular acidosis II. Caused by an impairment of bicarbonate absorption in the proximal tubule, proximal renal tubular acidosis (pRTA) is characterized by a decreased renal HCO3(-) threshold. pRTA-OA is an extremely rare autosomal recessive syndrome characterized by short stature, profound pRTA, mental retardation, bilateral glaucoma, cataracts and bandkeratopathy. Note=Loss of interaction with and stimulation by CA4 is the cause of retinitis pigmentosa type 17 (RP17).
Sequence similaritiesBelongs to the anion exchanger (TC 2.A.31) family.
Post-translational modificationsPhosphorylation of Ser-1026 by PKA increases the binding of CA2 and changes the Na(+):HCO3(-) stoichiometry of the transporter from 3:1 to 2:1. Phosphorylation of Thr-49 regulates isoform 1 conductance. N-glycosylation is not necessary for the transporter basic functions.