Tg(Myh6-SLC9A1*)8Gad

Mice with this transgene overexpress a mutant form of human solute carrier family 9 (sodium/hydrogen exchanger), member A1 (SLC9A1; formerly NHE1) in the myocardium. The transgene contains a 5.5-kb mouse genomic DNA fragment that encompasses the promoter of the myosin, heavy polypeptide 6, cardiac muscle, alpha (Myh6) gene driving expression of a 2551-bp cDNA encoding C-terminally hemagglutinin- (HA-) tagged human SLC9A1 in which four positively charged amino acids in the cytoplasmic regulatory domain (lysine at amino acid position 641 and arginine at positions 643, 645 and 647) have been replaced by the negatively-charged glutamic acid (K641E, R643E, R645E, R647E). These substitutions increase the protein's Na+ H+ transporter activity by shifting its pH preference toward the alkaline and by interfering with its regulation by calmoduolin. (J:82809, J:125924)