The Ple53-EGFP transgene (pEMS1199) was designed with the 3520 bp Ple53 minipromoter (DCX-B; derived from a portion of the promoter of the DCX gene from the doublecortin (DCX) gene) upstream of a minimal F5 mutant-frt site, an enhanced green fluorescent protein (with mutated TAA->TTA stop), a nuclear localization signal, a second minimal frt site, an SV40 early polyA signal, and a human HPRT complementary sequence (containing exon1, intron1, exon2, and part of intron2). This construct was targeted as a single copy knockin to the Hprtb-m3 mutant locus on the X chromosome. EGFP-immunoreactivity is detected most strongly in the neurogenic cells of the rostral migratory stream (RMS).