The phylogeny of the tribe Hyoscyameae based on complete plastomes and the evolution of the cox1 intron

ZUBKO, MIKHAJLO K.; IBAÑEZ, VERÓNICA NOÉ; GANDINI, CAROLINA LÍA; SANCHEZ-PUERTA, MARÍA VIRGINIA

Congreso; International SOL Meeting 2020; 2020

The tribe Hyoscyameae (Solanaceae) tribe comprises eight genera with twocenters of diversity: the Mediterranean-Turanian region (Atropa and Archihyoscyamus) and the Tibetan Plateau area (Przewalskia, Anisodus, and Atropanthe).The genus Scopolia includes species with disjunct distribution in eastern Asia and in the Mediterranean basin. Previous studies based on morphological or molecular characters were not able to resolve the phylogenetic affiliations of the tribe. Here, we assembled the complete chloroplast genome of Scopolia carniolica, the second species of the genus to be described. Using publicly available chloroplast genomes we performed genomic comparisons and examined the phylogenetic relationships for seven of the eight genera of Hyoscyameae. Gene content was identical across the tribe with small differences in genome length. The phylogeny of the tribe was highly resolved, with strong support for relationships among genera.The major advancements included strongly-supported phylogenetic affiliations of Atropanthe, Anisodus, and Hyoscyamus.We also studied the Hyoscyameae phylogeny using a nuclear marker, theinternal transcribed spacer 2 (ITS2). Interestingly, even though theITS2 tree was poorly resolved in general; it recovered all genera as monophyletic, except for Scopolia,which was paraphyletic in respect to Physochlaina. Finally, we re-interpreted the mitochondrial cox1 intron evolution. Two independent, intrafamilial, horizontal acquisitions were inferred, one in the ancestor of Przewalskia, Physochlaina and S. japonica,and another in Hyoscyamus with no intron losses.