Cre-mediated excision of the parental Synmtm1(KOMP)Vlcg allele resulted in the removal of the neomycin selection cassette and exons 2 and 3, leaving behind the inserted lacZ reporter sequence. Further information on targeting strategies used for this and other IKMC alleles can be found at http://www.informatics.jax.org/mgihome/nomen/IKMC_schematics.shtml.
RT-PCR analysis of mRNA from skeletal muscle of homozygous mutant and control mice showed that the transcript is absent from the homozygotes but present in controls. Western blot analysis of protein supernatants prepared from extracts of tibialis anterior muscles confirmed the absence of encoded protein in homozygous mutant muscles.