Horizontally transferred mitochondrial DNA tracts become circular by microhomology-mediated repair pathways
© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.
Publié dans: | The New phytologist. - 1979. - 243(2024), 6 vom: 25. Sept., Seite 2442-2456 |
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Auteur principal: | |
Autres auteurs: | , , |
Format: | Article en ligne |
Langue: | English |
Publié: |
2024
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Accès à la collection: | The New phytologist |
Sujets: | Journal Article Lophophytum Balanophoraceae HGT MMBIR Santalales mtDNA multichromosomal DNA, Mitochondrial DNA, Circular |
Résumé: | © 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation. The holoparasitic plant Lophophytum mirabile exhibits remarkable levels of mitochondrial horizontal gene transfer (HGT). Gathering comparative data from other individuals and host plants can provide insights into the HGT process. We sequenced the mitochondrial genome (mtDNA) from individuals of two species of Lophophytum and from mimosoid hosts. We applied a stringent phylogenomic approach to elucidate the origin of the whole mtDNAs, estimate the timing of the transfers, and understand the molecular mechanisms involved. Ancestral and recent HGT events replaced and enlarged the multichromosomal mtDNA of Lophophytum spp., with the foreign DNA ascending to 74%. A total of 14 foreign mitochondrial chromosomes originated from continuous regions in the host mtDNA flanked by short direct repeats. These foreign tracts are circularized by microhomology-mediated repair pathways and replicate independently until they are lost or they eventually recombine with other chromosomes. The foreign noncoding chromosomes are variably present in the population and likely evolve by genetic drift. We present the 'circle-mediated HGT' model in which foreign mitochondrial DNA tracts become circular and are maintained as plasmid-like molecules. This model challenges the conventional belief that foreign DNA must be integrated into the recipient genome for successful HGT |
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Description: | Date Completed 22.08.2024 Date Revised 22.08.2024 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1469-8137 |
DOI: | 10.1111/nph.19984 |