Organelle-to-Nucleus DNA Transfers in Black Cottonwood and Wine Grape

Our previous studies revealed that nuclear genome of Arabidopsis and rice contains multiple plastid and/or mitochondrial DNA (ptDNA and mtDNA, respectively) splinters with intact copies of many orqanellar genes, where some of them, at least, are transcribed. In these studies, comparison of the plastid genome of black cottonwood (Populus trichocarpa), both plastid and mitochondria genomes of wine grape (Vitis vinifera) with the corresponding nuclear genome revealed many “traces” of organellar DNA: 73% of black cottonwood plastid genome, 90% and 51% of wine grape plastid and mitochondria genomes, respectively, are present in nuclear genome in a form of multiple DNA fragments containing complete or partial copies of organellar protein coding genes. Results obtained suggest that nuclear copy of wine grape mitochondria rpl14 gene is expressed and it encodes ribosom L14 protein targeted to the mitochondria.