An 20aa Peptide sequence near the N-terminus of rat AE-1. The 20 AA rat control peptide is 90% conserved in mouse, 75% in human and 70% in bovine AE1. No significant sequence homology is detected with other AE or other proteins. Antibody crossreactivity in various species is not established. Control peptides, because of their low MW (<3kD), are not suitable for Western. It should be used for ELISA or antibody blocking to confirm antibody specificity.
Anion exchangers (AE) are membranes proteins involved in the regulation of intracellular pH, cell volume regulation as well as in transepithelial acid/base transport. AE proteins are sodium-independent exchangers that mediates one-for-one exchange of extracellular Cl- for intracellular HCO3- ions resulting in intracellular acidification. AE proteins are encoded by a family of at least three related genes (AE1, AE2, and AE3). Numerous alternatively spliced isoforms of each AE gene are expressed in various tissues. AE proteins are exemplified by a large N-terminal cytoplasmic domain (~40-75kD) that provides binding sites for cytoskeleton protein, glycolytic enzymes and hemoglobin. The N-terminal cytoplasmic domains of AE2 are AE3 are more closely related than AE1. In fact, AE1 N-terminus is 300 aa shorter than both the AE2 and AE3. The C-terminal TM domain (~55kD) is highly conserved (~70% identity) among various AE, spans the lipid bilayer 12-14 times, and is able to mediate anion exchange by itself.
AE1 protein (also know as band 3) is the most abundant protein in red cell membrane. AE1 gene has been cloned and characterized from a variety of species including mouse, rat, human, and chicken. Human AE1 gene (chromosome 17q21-qter) encodes for a protein of 911 aa (rat 927 aa; mouse 929 aa). Several isoforms of AE1 are also transcribed. AE1 is primarily expressed in red cells and kidney. AE1 is dimeric in solution. Defects in AE1/band3 gene are the cause of hereditary ovalocystosis (HO)-a disease associated with high degree of membrane rigidity.
