Complete Chloroplast Genome Of Dendrosenecio Brassiciformis And Its Phylogenetic Position Within Asteraceae

Dendrosenecio brassiciformis is an upright monocarpic plant which is endemic to Aberdares Mountain in Kenya. The plant grows in a mixed population of L. telekii and L. aberderica. It’s an exceptional example of convergent evolution whereby the unusual features of this species such as water storage in pith of the stem, massive leaf-rosette; nyctinastic leaf movement and retaining of dead foliage around the stem are as a result of evolutionary response to a challenging habitat. However, there is little genetic information about D. brassiciformis thus making phylogenetic identification and evolutionary studies difficult. So far only one species(Jacobaea vulgaris) from the Senecioneae tribe has been completely sequenced and analyzed. Due to the recent advancement in the use of next generation sequencing technique whereby the cost has dramatically fallen and increase in accuracy the genome of D.brassiciformis was sequenced using illumina sequencing technologies Phylogenetic analyses for the species and other 9 Asteraceae and 1 Solanaceae species using the inverted repeat, small single copy, large single copy regions and whole chloroplast genome sequence were also conducted. The results indicated that chloroplast genome of D.brassiciformis is a circular molecule of 150555 base pairs with a quadripartite structure containing two single copy regions, a large single copy (83376 bp) and a small single copy region (13599 bp) separated by inverted repeat regions (23700 bp). The overall GC content is 37.5%. The genome contains 121 unique genes and 19 are duplicated in the inverted repeat region with gene organization similar to other Asteraceae chloroplast genome. Phylogenetic analyses demonstrated a sister relationship between D.brassiciformis and Jacobaea vulgaris. Therefore, our study presents the second whole plastome of Senecioneae tribe and conducted phylogenetic analyses. The availability of this complete chloroplast genome will be useful for further investigation of the chloroplast genome of Dendrosenecio and other higher plant.