Truncated Non-Nuclear Transposable Elements in Grapevine: A Mini Review

Abstract

Abstract In this mini-review we present insight to the non-nuclear transposable elements and in silico analysis of miniature inverted transposable elements (MITEs) in the grapevine mitochondrial genome. Here we report the identification of 17 truncated sequences in grapevine (Vitis vinifera L.) mitochondrial genome which expectedly belongs to the four ancient transposon families (hAT, Tc1Mariner, Mutator and PIF/Harbinger). Some sequences with a high rate of homology in chloroplast and nuclear genomes were also identified. Thus, it suggests the intercellular gene transfer between these three organelles. These partial sequences showed a high level of similitude with full MITE sequences, and they were found in their inner region, supporting their MITE origin. Further analysis revealed these sequences in other life kingdoms (including eubacteria and archaea), which indicates their ancient origin. Further research showed that 13 out of the 17 sequences are conserved domains of the genes where they are located, suggesting their contribution to gene evolution. Therefore, we suppose that more studies of nature, origin and functional meaning of these sequences and their fusion with genes are necessary. In the light of our observations it will be useful for further studies of V. vinifera genome organizing and systematics, as well as for other species.