The complete chloroplast genome sequence of Kandelia obovata (Rhizophoraceae)

A comparison of 25 complete chloroplast genomes between sister mangrove species Kandelia obovata and Kandelia candel geographically separated by the South China Sea

In 2003, Kandelia obovata was identified as a new mangrove species differentiated from Kandelia candel. However, little is known about their chloroplast (cp) genome differences and their possible ecological significance. In this study, 25 whole cp genomes, with seven samples of K. candel from Malaysia, Thailand, and Bangladesh and 18 samples of K. obovata from China, were sequenced for comparison. The cp genomes of both species encoded 128 genes, namely 83 protein-coding genes, 37 tRNA genes, and eight rRNA genes, but the cp genome size of K. obovata was ~2 kb larger than that of K. candle due to the presence of more and longer repeat sequences. Of these, tandem repeats and simple sequence repeats exhibited great differences. Principal component analysis based on indels, and phylogenetic tree analyses constructed with homologous protein genes from the single-copy genes, as well as 38 homologous pair genes among 13 mangrove species, gave strong support to the separation of the two species within the Kandelia genus. Homologous genes ndhD and atpA showed intraspecific consistency and interspecific differences. Molecular dynamics simulations of their corresponding proteins, NAD(P)H dehydrogenase chain 4 (NDH-D) and ATP synthase subunit alpha (ATP-A), predicted them to be significantly different in the functions of photosynthetic electron transport and ATP generation in the two species. These results suggest that the energy requirement was a pivotal factor in their adaptation to differential environments geographically separated by the South China Sea. Our results also provide clues for future research on their physiological and molecular adaptation mechanisms to light and temperature.

Characterization of the complete chloroplast genome of Carallia diplopetala (Rhizophoraceae)

Carallia diplopetala (Rhizophoraceae) is an important economic tree species narrowly distributed endemic to East Asia. In this study, We generate the complete chloroplast genome of C. diplopetala using next-generation sequencing technology, which is 162,052 bp in size and consists of a large single copy (LSC) of 89,556 bp and a small single copy (SSC) of 18,814 bp, separated a pair of inverted repeats (IRb and IRa) of 26,841 bp. The overall GC content is 36.4%. A total of 130 genes are annotated, including 83 protein-coding genes, 37 tRNAs, eight rRNAs and two pseudogenes (ψycf1 and ψrps19). The phylogenetic analysis indicated that C. diplopetala and C. brachiate formed a monophyletic clade with strong support and then sister to Pellacalyx yunnanensis. The plastome of C. diplopetala will provide informative genomic resources for further conservation applications.

The complete chloroplast genome sequence of Tapiscia sinensis (Staphyleaceae)

Tapiscia sinensis, belong to Tapisciaceae, is endangered tree endemic to China. Here, we provide the complete plastid genomic data of T. sinensis with the aim of providing data for future conservation efforts research and revealing its phylogenetic position. The complete chloroplast sequence is 161,093 bp, including a large single-copy (LSC) region of 87,782 bp, a small single-copy (SSC) region of 18,517 bp, a pair of invert repeats (IR) regions of 27,387 bp. Plastid genome contains 131 genes, 85 protein-coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic analysis base on 19 plastid genomes indicates that T. sinensis located Malvids branch, and is more closely related to the species of the order Sapindales than those of the order Malvales.

Complete chloroplast genome sequence of Bougainvillea Spectabilis (Nyctaginaceae)

Bougainvillea spectabilis is an important ornamental plant in tropical and subtropical regions, whose complex and diverse germplasm has brought great difficulties to variety selection and identification. Here, to provide data support for the identification of the relationship between cultivars of B. spectabilis, we sequenced the chloroplast genome of B. spectabilis. The chloroplast genome is 154,520 bp in length, including a large single-copy (LSC) region of 88,101 bp and small single-copy (SSC) region of 17,729 bp, and a pair of invert repeats (IR) regions of 24,171 bp. The chloroplast genome contains 129 genes, including 83 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The phylogenetic analysis based on 14 chloroplast genome demonstrated a close relationship between B. spectabilis and other plant species in Caryophyllales. The chloroplast genome will help for further of taxonomy research and provide data support for the identification of genetic relationship among different cultivars of B. spectabilis.