A cDNA encoding enhanced green fluorescent protein was inserted 5' of the initiating ATG codon in exon 2 and a PGK-neor cassette into intron 2 of the myosin, heavy polypeptide 9, non-muscle (Myh9) gene. The selection cassette has been deleted by Cre recombinase-mediated excision. Immunoblot analysis demonstrates that levels of wild-type and EGFP-tagged MYH9 protein are similar in lungs of heterozygous mutant mice. (J:175367)