Hif1a^tm1Mcs

Exon 1, containing the ATG, was replaced with a c-Myc epitope tagged Epas1 cDNA and floxed PGK-neo such that knock in expression depends upon the endogenous regulatory sequence. Mutant ES cells expressed reduced levels of endogenous protein and proved to be hypomrphic. RACE confirmed that a novel transcript was created originating from the PGK promoter. This transcript contained an in-frame methionine codon 11 amino acids downstream of the ATG, wich resulting in deletion of three lysine residues within the DNA binding domain. EMSA showed reduced DNA binding-activity in mutant ES cells. (J:97164)