The complete chloroplast genome sequence of Tribulus terrestris, an important traditional Chinese medicine

The complete chloroplast genome sequence of Zygophyllum brachypterum (Zygophyllaceae) reveals its distinctive characteristics and evolutionary implication

Zygophyllum brachypterum Karelin & Kirilov belongs to Zygophyllaceae and is mainly distributed in the desert regions of Central Asia, Mongolia, and Northwest China. The species is valuable in exploring the adaptations of Zygophyllaceae plants to salt stress in ecological environments. In this study, we report the complete chloroplast (cp) genome of Z. brachypterum. The entire cp genome was 104590 bp in length, with a large single-copy region (LSC, 79170 bp), a small single-copy region (SSC, 16778 bp), and two inverted repeats (IRa/IRb) of 4321 bp each. A total of 106 genes were detected, among which seven were located in the IRs, and 65, 30, and 4 were protein-coding, tRNA, and rRNA genes, respectively. Notably, eleven genes encoding the subunits of NAD(P)H dehydrogenase complex (NDH) were absent. Phylogenetic analysis indicated that Z. brachypterum belonged to Zygophylloideae (Zygophyllaceae). Furthermore, it was closely related to Z. fabago and Z. kansuense.

Comparative chloroplast genomics provides insights into the genealogical relationships of endangered Tetraena mongolica and the chloroplast genome evolution of related Zygophyllaceae species

A comprehensive understanding of genetic background for rare species will provide an important theoretical basis for the future species management, monitoring and conservation. Tetraena mongolica is restrictedly distributed in the western Ordos plateau of China and has been listed as a national protected plant. We generated 13 chloroplast (cp) genomes of T. mongolica (size range of 106,062-106,230 bp) and conducted a series of comparative analyses of six Zygophyllaceae cp genomes. T. mongolica cp genome exhibited a quadripartite structure with drastically reduced inverted repeats (IRs, 4,315 bp) and undergone the loss of a suit of ndh genes and a copy of rRNAs. Furthermore, all the T. mongolica populations were divided into two genetic groups based on complete cp phylogenomics. In addition, notably variable genome size, gene order and structural changes had been observed among the six Zygophyllaceae cp genomes. Overall, our findings provide insights into the cp genome evolution mode and intraspecific relationships of T. mongolica, and provide a molecular basis for scientific conservation of this endangered plant.

The complete chloroplast genome of Tripterygium wilfordii Hook. f. (Celastraceae)

Tripterygium wilfordii is a perennial vine plant with medicinal value and belongs to the family of Celastraceae. In this study, we sequenced and analyzed the complete chloroplast genome of T. wilfordii. The chloroplast genome was 156,700 bp in length with a GC content of 37.47%. It contained two inverted repeat (IR) regions of 26,461 bp; each region was separated by large single-copy and small single-copy regions of 85,409 bp and 18,369 bp, respectively. In total, we annotated 134 unique genes, consisting of 89 protein-encoding genes, 8 rRNAs and 37 tRNAs. Phylogenetic analysis revealed that T. wilfordii was sister to T. regelii in a clade of Tripterygiumii species that was sister to a clade of Euonymus species.