Phylogenomics and morphological evolution of the mega-diverse genus Artemisia (Asteraceae: Anthemideae): implications for its circumscription and infrageneric taxonomy.

BACKGROUND AND AIMS: Artemisia is a mega-diverse genus consisting of ~400 species. Despite its medicinal importance and ecological significance, a well-resolved phylogeny for global Artemisia, a natural generic delimitation and infrageneric taxonomy remain missing, owing to the obstructions from limited taxon sampling and insufficient information on DNA markers. Its morphological characters, such as capitulum, life form and leaf, show marked variations and are widely used in its infrageneric taxonomy. However, their evolution within Artemisia is poorly understood. Here, we aimed to reconstruct a well-resolved phylogeny for global Artemisia via a phylogenomic approach, to infer the evolutionary patterns of its key morphological characters and to update its circumscription and infrageneric taxonomy. METHODS: We sampled 228 species (258 samples) of Artemisia and its allies from both fresh and herbarium collections, covering all the subgenera and its main geographical areas, and conducted a phylogenomic analysis based on nuclear single nucleotide polymorphisms (SNPs) obtained from genome skimming data. Based on the phylogenetic framework, we inferred the possible evolutionary patterns of six key morphological characters widely used in its previous taxonomy. KEY RESULTS: The genus Kaschgaria was revealed to be nested in Artemisia with strong support. A well-resolved phylogeny of Artemisia consisting of eight highly supported clades was recovered, two of which were identified for the first time. Most of the previously recognized subgenera were not supported as monophyletic. Evolutionary inferences based on the six morphological characters showed that different states of these characters originated independently more than once. CONCLUSIONS: The circumscription of Artemisia is enlarged to include the genus Kaschgaria. The morphological characters traditionally used for the infrageneric taxonomy of Artemisia do not match the new phylogenetic tree. They experienced a more complex evolutionary history than previously thought. We propose a revised infrageneric taxonomy of the newly circumscribed Artemisia, with eight recognized subgenera to accommodate the new results.

The complete plastid genome sequence of Vaccinium japonicum (Ericales: Ericaceae), a deciduous broad-leaved shrub endemic to East Asia.

We here sequenced the complete plastid genome (plastome) of Vaccinium japonicum (Ericaceae), a deciduous broad-leaved shrub endemic to East Asia. This species has considerable practical economic value. The plastome of V. japonicum is assembled as a single contig (187,213 bp). A large single copy (104,637 bp) and a small single copy (3,000 bp) of the genome are separated by a pair of inverted repeats (39,788 bp). The genome consists of 135 genes, which include 88 protein coding, eight ribosomal RNA, and 39 transfer RNA genes. The plastome of V. japonicum is similar to that of Vaccinium macrocarpon in gene content and order. Our phylogenetic analysis revealed the phylogenetic position of V. japonicum in a highly supported clade of the genus Vaccinium together with other four congeners, V. bracteatum, V. vitis-idaea, V. uliginosum and V. macrocarpon.

Antioxidant activity in essential oils of Cnidium officinale makino and Ligusticum chuanxiong Hort and their inhibitory effects on DNA damage and apoptosis induced by ultraviolet B in mammalian cell.

BACKGROUND: Owing to their high volatile aroma, the dried rhizomes of Cnidium officinale (C. officinale) and Ligusticum chuanxiong (L. chuanxiong) are used as herbal drugs to treat blood pressure depressant, a deficiency disease of antivitamin, inhibition of small intestine sympathetic nerve and as cosmetics for skin care. However, little has been known about the protective effect of their essential oils against ultraviolet B (UVB)-induced DNA damage. METHODS: In this study, we report antioxidant activity of their essential oils using DPPH and ABTS scavenging assay. In addition, the composition of essential oils was measured by GC/MS. We also investigated whether these essential oils could inhibit UVB-induced DNA damage and apoptosis in the mammalian cell using intracellular DNA migration and expression level of phospho-H2A.X. RESULTS: Twenty constituents in the essential oil were identified and they showed good antioxidant properties, in that IC(50) value in DPPH and ABTS showed 6.79 and 7.33microg/ml and 1.58 and 1.58microg/ml in C. officinale and L. chuanxiong. Their treatment inhibited the migration of damaged DNA induced by UV-B; furthermore, they decreased p21 expression and increased cyclin D1 expression as apoptosis-regulatory genes. CONCLUSIONS: These results suggest that essential oils in C. officinale and L. chuanxiong may exert inhibitory effects on DNA damage and apoptosis induced by UVB through their high free radical scavenging ability.

Protective effect of the extracts from Cnidium officinale against oxidative damage induced by hydrogen peroxide via antioxidant effect.

The dried rhizomes of Cnidium officinale are used as herbal drugs in the treatment of pain, inflammation, menstrual disturbance and antivitamin deficiency disease, and also act as a blood pressure depressant. In addition, there are several reports suggesting that they have pharmacological properties to tumor metastasis and angiogenesis, and that they act as an inhibitor of high glucose-induced proliferation of glomerular mesangial cells. However, little has been known about the functional role of the extracts from C. officinale on oxidative DNA damage and apoptosis caused by ROS. In this work, we have investigated the DPPH radical, hydroxyl radical and intracellular ROS scavenging capacity, and Fe(2+) chelating activity of the extracts from C. officinale. In addition, we evaluated whether the extracts are capable of reducing H(2)O(2)-induced DNA and cell damage in the human skin fibroblast cell. These extracts showed a dose-dependent free-radical scavenging capacity and a protective effect on DNA damage and the lipid peroxidation causing the cell damage by ROS. These antioxidant activities and inhibitory effects of the extracts on DNA and cell damage may further explain that C. officinale is useful as a herbal medicine for cancer chemoprevention.

Phylogenetic, morphological, and chemotaxonomic incongruence in the North American endemic genus Echinacea.

The study of recently formed species is important because it can help us to better understand organismal divergence and the speciation process. However, these species often present difficult challenges in the field of molecular phylogenetics because the processes that drive molecular divergence can lag behind phenotypic divergence. In the current study we show that species of the recently diverged North American endemic genus of purple coneflower, Echinacea, have low levels of molecular divergence. Data from three nuclear loci and two plastid loci provide neither resolved topologies nor congruent hypotheses about species-level relationships. This lack of phylogenetic resolution is likely due to the combined effects of incomplete lineage sorting, hybridization, and backcrossing following secondary contact. The poor resolution provided by molecular markers contrasts previous studies that found well-resolved and taxonomically supported relationships from metabolic and morphological data. These results suggest that phenotypic canalization, resulting in identifiable morphological species, has occurred rapidly within Echinacea. Conversely, molecular signals have been distorted by gene flow and incomplete lineage sorting. Here we explore the impact of natural history on the genetic organization and phylogenetic relationships of Echinacea.

Cancer-preventive peptide lunasin from Solanum nigrum L. inhibits acetylation of core histones H3 and H4 and phosphorylation of retinoblastoma protein (Rb).

Lunasin, a unique 43 amino acid, 4.8 kDa cancer-chemopreventive peptide initially reported in soybean and now found in barley and wheat, has been shown to be cancer-chemopreventive in mammalian cells and in a skin cancer mouse model against oncogenes and chemical carcinogens. To identify bioactive components in traditional herbal medicines and in search for new sources of lunasin, we report here the properties of lunasin from Solanum nigrum L. (SNL), a plant indigenous to northeast Asia. Lunasin was screened in the crude extracts of five varieties of the medicinal plants of Solanaceae origin and seven other major herbal plants. An in vitro digestion stability assay for measuring bioavailability was carried out on SNL crude protein and autoclaved SNL using pepsin and pancreatin. A nonradioactive histone acetyltransferase (HAT) assay and HAT activity colorimetric assay were used to measure the inhibition of core histone acetylation. The inhibitory effect of lunasin on the phosphorylation of retinoblastoma protein (Rb) was determined by immunoblotting against phospho-Rb. Lunasin isolated from autoclaved SNL inhibited core histone H3 and H4 acetylation, the activities of the HATs, and the phosphorylation of the Rb protein. Lunasin in the crude protein and in the autoclaved crude protein was very stable to pepsin and pancreatin in vitro digestion, while the synthetic pure lunasin was digested at 2 min after the reaction. We conclude that lunasin is a bioactive and bioavailable component in SNL and that consumption of SNL may play an important role in cancer prevention.

The cancer preventive peptide lunasin from wheat inhibits core histone acetylation.

Lunasin is a unique 43-amino acid cancer preventive peptide initially reported in soybean and barley and has been shown to be chemopreventive in mammalian cells and in a skin cancer mouse model against oncogenes and chemical carcinogens. We report here the core histone H3- and H-acetylation inhibitory properties of lunasin from wheat, a new source of the peptide and from the livers of rats fed with lunasin-enriched wheat (LEW) to measure bioavailability. A non-radioactive histone acetyl transferase assay was used to measure inhibition of core histone acetylation. The presence of lunasin in wheat was established by Western blot and identified by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS). Lunasin isolated from wheat seeds at different stages of development inhibited core histone H3 and H4 acetylation in a dose-dependent manner. Lunasin extracted from liver of rats fed with lunasin-enriched wheat (LEW) also inhibited histone acetylation confirming that the peptide is intact and bioactive. The amounts of lunasin in the developing seeds and in the rat liver correlated extremely well with the extent of inhibition of core histone acetylation.