TDP-43 is an RNA-binding protein involved in all stages of RNA processing. It also plays an important role in pathophysiology of some neurodegenerative diseases including ALS and FTLD. The human gene encoding TDP-43 is TARDBP. It consists of six exons and five introns. After processing, there are eight possible mRNA variants, one of which encodes for TDP-43. In addition to TARDBP, there are five processed TDP-43 pseudogenes in human genome. We examined the phylogenetic relationships of mammalian TDP-43 orthologues. The evolutionary tree was based on mRNA sequences because protein sequences are too similar. We concluded that TDP-43 phylogeny is mostly analogous to the evolutionary relationships of mammalian species with a few exceptions. In addition, we also studied when the human TDP-43 pseudogenes 1, 2, 3 and 8 emerged during evolution. We established that all these pseudogenes are present in Old world monkeys and Apes. Pseudogene 1 is also conserved in New world monkeys. The same is likely true for pseudogene 2, while analyses of pseudogene 3 and 8 give unclear information on the origin of these two pseudogenes.
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