Sequence conservation of HOTAIR orthologues in mammals. (A) The sequences of HOTAIR orthologues are obviously conserved in primates but less well conserved in other animals (from UCSC Genome Browser). (B) Orthologues of the HOTAIR exons exist only in mammals. Exon1, exon3, exon4, exon5 and domain B of exon6 are better conserved than exon2, exon6 and domain A of exon6 (indicated by the darkness of the boxes). Note that the sequence of the exon6 orthologue is significantly shorter in rat than in other mammals and contains just two domains. The two boxes under each exon6 are domain A (right side) and domain B (left side), linked by a double line indicating a gap of 130 bp (unmatched part in the Infernal search). The gaps in exon6 of dolphin and dog also indicate unmatched parts in the Infernal search. The double slashes in the schematic of the dolphin gene indicate long introns. (C) The order and orientation of HOTAIR and its neighbouring HoxC genes in mammals. X: HoxC is absent.
He et al. BMC Evolutionary Biology 2011 11:102 doi:10.1186/1471-2148-11-102