Unprecedented organelle genomic variations in morning glories reveal independent evolutionary scenarios of parasitic plants and the diversification of plant mitochondrial complexes

作者：Yanxiang Lin, Pan Li, Yuchan Zhang, Delara Akhter, Ronghui Pan, Zhixi Fu, Mingqing Huang, Xiaobo Li, Yanlei Feng · 发表于：BMC Biology · 年份：2022 · DOI：10.1186/s12915-022-01250-1 · 被引用次数：30 · 研究领域：Plant Parasitism and Resistance、Plant Diversity and Evolution、Plant Molecular Biology Research

BACKGROUND: The morning glories (Convolvulaceae) are distributed worldwide and produce economically important crops, medicinal herbs, and ornamentals. Members of this family are diverse in morphological characteristics and trophic modes, including the leafless parasitic Cuscuta (dodders). Organelle genomes were generally used for studying plant phylogeny and genomic variations. Notably, plastomes in parasitic plants always show non-canonical features, such as reduced size and accelerated rates. However, few organelle genomes of this group have been sequenced, hindering our understanding of their evolution, and dodder mitogenome in particular. RESULTS: We assembled 22 new mitogenomes and 12 new plastomes in Convolvulaceae. Alongside previously known ones, we totally analyzed organelle genomes of 23 species in the family. Our sampling includes 16 leafy autotrophic species and 7 leafless parasitic dodders, covering 8 of the 12 tribes. Both the plastid and mitochondrial genomes of these plants have encountered variations that were rarely observed in other angiosperms. All of the plastomes possessed atypical IR boundaries. Besides the gene and IR losses in dodders, some leafy species also showed gene and intron losses, duplications, structural variations, and insertions of foreign DNAs. The phylogeny reconstructed by plastid protein coding sequences confirmed the previous relationship of the tribes. However, the monophyly of 'Merremieae' and the sister group of Cuscuta remained un...