Dlg4^tm1Grnt

A stop codon was introduced into sequence encoding the PDZ3 domain. In addition, a cassette containing IRES-lacZ and neo was inserted downstream to replace sequence putatively essential for subcellular localization. An RNAse protection verified transcription of the targeted allele. While low levels of the mutant protein containing the PDZ1 and PDZ2 domains were detected by Western blot analysis of homozygous mutant forebrain extracts, the mutant protein was undetected in the synaptosome, synaptic plasma membrane, and posynaptic density fractions. Comparisons with previous results of in situ hybridization studies showed the expression pattern of beta-galactosidase to resemble that of the endogenous gene. (J:77693)