Recent gain of a snoRNA in a ribosomal protein of mitochondrial origin. The tree (top graphic) indicates depth of association of SNORA58 with its host introns. Circles indicate the distribution of SNORA58, while squares indicate distribution of the protein. MRPL3 [47-49] and NDC1  can be traced to the LECA, while UBAP2L is traceable to the vertebrate ancestor (data not shown). Expression data  indicate all three host genes are widely expressed in amniotes (Additional file 4). Grey squares indicate SNORA58 presence in the intron. The bottom graphic shows the position of SNORA58 in the introns of each gene is indicated by arrowheads. Gene orientation is indicated by < and >. The gene structure in the figure is from human. LECA—Last Eukaryotic Common Ancestor, VA—Vertebrate Ancestor, MA—Mammalian Ancestor, PR – Primate ancestor.
Hoeppner and Poole BMC Evolutionary Biology 2012 12:183 doi:10.1186/1471-2148-12-183