Downregulated-in-adenoma
Encyclopedia
The downregulated-in-adenoma (DRA) is a membrane protein
in intestinal cells
. It is an anion exchanger
and a member (SLC26A3
) of the sulfate anion transporter (SAT) family. It mediates chloride
and bicarbonate
exchange and additionally transports sulfate
and other anions at the apical membrane, part of the plasma membrane of enterocytes. The congenital absence of this membrane protein results in an autosomal recessive disorder
called congenital chloridorrhea or congenital chloride diarrhea
(CLD). It is different from the anion exchanger that present in erythrocytes, renal tubule, and several other tissues.
Membrane protein
A membrane protein is a protein molecule that is attached to, or associated with the membrane of a cell or an organelle. More than half of all proteins interact with membranes.-Function:...
in intestinal cells
Enterocyte
Enterocytes, or intestinal absorptive cells, are simple columnar epithelial cells found in the small intestines and colon. A glycocalyx surface coat contains digestive enzymes. Microvilli on the apical surface increase surface area for the digestion and transport of molecules from the intestinal...
. It is an anion exchanger
Ion exchange
Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex. In most cases the term is used to denote the processes of purification, separation, and decontamination of aqueous and other ion-containing solutions with solid polymeric or mineralic 'ion...
and a member (SLC26A3
SLC26A3
Solute carrier family 26, member 3, also known as SLC26A3, or DRA is a human gene.-Further reading:...
) of the sulfate anion transporter (SAT) family. It mediates chloride
Chloride
The chloride ion is formed when the element chlorine, a halogen, picks up one electron to form an anion Cl−. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. The chloride ion, and its salts such as sodium chloride, are very soluble in water...
and bicarbonate
Bicarbonate
In inorganic chemistry, bicarbonate is an intermediate form in the deprotonation of carbonic acid...
exchange and additionally transports sulfate
Sulfate
In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...
and other anions at the apical membrane, part of the plasma membrane of enterocytes. The congenital absence of this membrane protein results in an autosomal recessive disorder
Dominance relationship
Dominance in genetics is a relationship between two variant forms of a single gene, in which one allele masks the effect of the other in influencing some trait. In the simplest case, if a gene exists in two allelic forms , three combinations of alleles are possible: AA, AB, and BB...
called congenital chloridorrhea or congenital chloride diarrhea
Congenital chloride diarrhea
Congenital chloride diarrhea is a genetic disorder due to an autosomal recessive mutation on chromosome 7. The mutation is in downregulated-in-adenoma , a gene that encodes a membrane protein of intestinal cells. The protein belongs to the solute carrier 26 family of membrane transport proteins...
(CLD). It is different from the anion exchanger that present in erythrocytes, renal tubule, and several other tissues.
External links
- Sterling, D., et al. (2002). The functional and physical relationship between the downregulated in adenoma bicarbonate transporter and carbonic anhydrase II. Am J Physiol.
- Alrefai WA, et al. (2007) Molecular cloning and promoter analysis of downregulated in adenoma (DRA) Am J Physiol.