Thus it is possible that these miRNAs derive from duplication events and the duplicated miRNAs may evolve into new sequences that acquire new functions.
This is reminiscent of a newly arising miRNA derived from duplication of progenitor genes [3], [4].
In Arabidopsis, miRNA-like genes have been characterized in which multiple phased ∼21-nt siRNAs are processed from a single foldback structure derived from duplication of progenitor genes [4], [12].
Orthologs derive from a common ancestor by speciation, in contrast to paralogs, which derive from duplication.
Because the EMPs derive from duplication events, AMEL, AMBN and ENAM are phylogenetically related [ 18].
Several lineages showing significantly greater evolutionary change than their sister lineages or clades derived from duplication events.
Yet, note that 11% of the miR genes have clearly been derived from duplication of miR genes.
Furthermore, most of the hub kinases were not derived from duplication events, with the exception of BRL2 and MPK3 (dispersed duplication) and CDK (segmental duplication).
MHC molecules encoded by individual loci derived from duplication would then have become available to co-evolve with certain lymphocytes' receptors, most probably various forms of γδ TCRs.
Interestingly, the genomic comparison between the plasmid pSYMBR3459a and the chromosome of B. phenoliruptrix showed 154 common clusters, most of which were not derived from duplication processes.
In Drosophila, E75 and E78, orthologous of Rev-Erb, are derived from duplication events that did not occur in the vertebrate lineage [ 33].
