Myh9^{tm6.1(EGFP/MYH9*)Rsad}

A cDNA encoding a fusion protein comprising enhanced green fluorescent protein (EGFP) joined to the N-terminus of a mutant human myosin, heavy polypeptide 9, non-muscle (MYH9) protein, followed by the SV40 polyadenylation signal and a loxP-flanked PGK-neor cassette, was inserted at the ATG translation initiation site in the second exon of the mouse Myh9 gene. An mRNA encoding GFP-tailed mutant human MYO9 is thus expressed from the endogenous mouse promoter in place of the mouse Myo9 transcript. The mutation, which replaces arginine with cysteine at amino acid position 702, in the motor domain of the globular head of the myosin protein (R702C), is associated with a human MYH9-related disease (MYH9-RD). The selection cassette has been deleted by Cre recombinase-mediated excision. Immunoblot analysis reveals that the EGFP-tagged human MYH9 protein is expressed at ~80% of the level of the endogenous mouse protein in lung, leukocyte/platelet fraction, megakaryocytes and neutrophils of heterozygous mutant mice. (J:175367)