Fig. 5.
Summary of Mkrn1-p1 and Mkrn1 data. (A) Chromosome 5 Mkrn1-p1 pseudogene. BLAST, RT-PCR expression, and DNA methylation analyses show that Mkrn1-p1 is transcriptionally silent (CH3, complete methylation). The presence of three conserved noncoding sequences (CNSs, asterisks) putatively deleted upon sxl transgene insertion (6) may contribute to deregulation of unidentified flanking genes (arrows) to cause the observed phenotype. (B) Chromosome 6 Mkrn1 locus. A 0.75-kb Mkrn1 mRNA isoform, resulting from a cryptic polyadenylation signal (triangle) in Mkrn1 intron 3, explains the misidentification of a Mkrn1-p1 transcript (6). CpG, unmethylated CpG-island at 5′ Mkrn1; E, EcoRI; K, KpnI; S, SacI; +, level of expression of Mkrn1 isoforms.