Figure 6
From: Bidirectional transcription of a novel chimeric gene mapping to mouse chromosome Yq
Genomic arrangement of Xmr and Xlr. 
indicates the position and orientation of LINE elements. Xmr contains a LINE insertion in intron 7 that is not present in Xlr and presumably postdates Xmr/Xlr divergence. There are two transcriptional variants of Xmr, neither of which splice in an exon corresponding to Xlr exon 5. This exon encodes the nuclear localisation signal, thus Xmr has lost the ancestral nuclear pattern of expression. The longer Xmr isoforms has 4 unique 5' exons.