Target sequence capture data shed light on the deeper evolutionary relationships of subgenus Chamaecerasus in Lonicera (Caprifoliaceae).

The genus Lonicera L. is widely distributed in the north temperate zone and is well-known for its high species richness and morphological diversity. Previous studies have suggested that many sections of Lonicera are not monophyletic and phylogenetic relationships within the genus are still poorly resolved. In this study, we sampled 37 accessions of Lonicera, covering four sections of subgenus Chamaecerasus plus six outgroup taxa, to recover the main clades of Lonicera based on sequences of nuclear loci generated by target enrichment and cpDNA from genome skimming. We found extensive cytonuclear discordance across the subgenus. Both nuclear and plastid phylogenetic analyses supported subgenus Chamaecerasus sister to subgenus Lonicera. Within subgenus Chamaecerasus, sections Isika and Nintooa were each polyphyletic. Based on the nuclear and chloroplast phylogenies, we propose to merge Lonicera korolkowii into section Coeloxylosteum and Lonicera caerulea into section Nintooa. In addition, Lonicera is estimated to have originated in the mid Oligocene (26.45 Ma). The stem age of section Nintooa was estimated to be 17.09 Ma (95% HPD: 13.30-24.45). The stem age of subgenus Lonicera was estimated to be 16.35 Ma (95% HPD: 14.12-23.66). Ancestral area reconstruction analyses indicate that subgenus Chamaecerasus originated in East Asia and Central Asia. In addition, sections Coeloxylosteum and Nintooa originated in East Asia, with subsequent dispersals into other areas. The aridification of the Asian interior likely promoted the rapid radiation of sections Coeloxylosteum and Nintooa within this region. Moreover, our biogeographic analysis fully supports the Bering and the North Atlantic Land Bridge hypotheses for the intercontinental migrations in the Northern Hemisphere. Overall, this study provides new insights into the taxonomically complex lineages of subgenus Chamaecerasus and the process of speciation.

Plastome structure, phylogenomic analyses and molecular dating of Arecaceae.

Arecaceae is a species-rich clade of Arecales, while also being regarded as a morphologically diverse angiosperm family with numerous species having significant economic, medicinal, and ornamental value. Although in-depth studies focused on the chloroplast structure of Arecaceae, as well as inferring phylogenetic relationships using gene fragments, have been reported in recent years, a comprehensive analysis of the chloroplast structure of Arecaceae is still needed. Here we perform a comprehensive analysis of the structural features of the chloroplast genome of Arecaceae, compare the variability of gene sequences, infer phylogenetic relationships, estimate species divergence times, and reconstruct ancestral morphological traits. In this study, 74 chloroplast genomes of Arecaceae were obtained, covering five subfamilies. The results show that all chloroplast genomes possess a typical tetrad structure ranging in size between 153,806-160,122 bp, with a total of 130-137 genes, including 76-82 protein-coding genes, 29-32 tRNA genes, and 4 rRNA genes. Additionally, the total GC content was between 36.9-37.7%. Analysis of the SC/IR boundary indicated that the IR region underwent expansion or contraction. Phylogenetic relationships indicate that all five subfamilies in Arecaceae are monophyletic and that Ceroxyloideae and Arecoideae are sister groups (BS/PP = 100/1). The results of molecular dating indicate that the age of the crown group of Arecaceae is likely to be 96.60 [84.90-107.60] Ma, while the age of the stem group is 102.40 [93.44-111.17] Ma. Reconstruction of ancestral traits indicate that the ancestral characteristics of the family include monoecious plants, one seed, six stamens, and a smooth pericarp.

Phylogenomic analyses of the East Asian endemic Abelia (Caprifoliaceae) shed insights into the temporal and spatial diversification history with widespread hybridization.

BACKGROUND AND AIMS: Abelia (Caprifoliaceae) is a small genus with five species, including one artificial hybrid and several natural hybrids. The genus has a discontinuous distribution in Mainland China, Taiwan Island and the Ryukyu Islands, providing a model system to explore the mechanisms of species dispersal in the East Asian flora. However, the current phylogenetic relationships within Abelia remain uncertain. METHODS: We reconstructed the phylogenetic relationships within Abelia using nuclear loci generated by target enrichment and plastomes from genome skimming. Divergence time estimation, ancestral area reconstruction and ecological niche modelling (ENM) were used to examine the diversification history of Abelia. KEY RESULTS: We found extensive cytonuclear discordance across the genus. By integrating lines of evidence from molecular phylogenies, divergence times and morphology, we propose to merge Abelia macrotera var. zabelioides into A. uniflora. Network analyses suggested that there have been multiple widespread hybridization events among Abelia species. These hybridization events may have contributed to the speciation mechanism and resulted in the high observed morphological diversity. The diversification of Abelia began in the early Eocene, followed by A. chinensis var. ionandra colonizing Taiwan Island during the Middle Miocene. The ENM results suggested an expansion of climatically suitable areas during the Last Glacial Maximum and range contraction during the Last Interglacial. Disjunction between the Himalayan-Hengduan Mountain region and Taiwan Island is probably the consequence of topographical isolation and postglacial contraction. CONCLUSIONS: We used genomic data to reconstruct the phylogeny of Abelia and found a clear pattern of reticulate evolution in the group. In addition, our results suggest that shrinkage of postglacial range and the heterogeneity of the terrain have led to the disjunction between Mainland China and Taiwan Island. This study provides important new insights into the speciation process and taxonomy of Abelia.

The complete chloroplast genome sequence of Phyllagathi hainanensis (Melastomataceae) and phylogenetic analysis.

Phyllagathi hainanensis (Merr. et Chun) C. Chen is a small shrubs of Melastomataceae. It is only distributed in Hainan provinces of China. The complete chloroplast genome of P. hainanensis is reported in this study. The complete chloroplast genome of P. hainanensis is 156,123 bp in length with a typical quadripartite structure, consisting of a large single-copy region (LSC, 85,497 bp), a single-copy region (SSC, 17,076 bp), and a pair of inverted repeats (IRs, 26,775 bp). There are 129 genes annotated, including 37 transfer RNA genes, 8 ribosomal RNA genes, and 84 proteincoding genes. The complete plastome sequence of P. hainanensis will provide a useful resource for phylogenetic studies in Melastomataceae.

Characterization of the complete chloroplast genome of Scorpiothyrsus erythrotrichus (Melastomataceae), an endemic to Hainan.

Scorpiothyrsus erythrotrichus belongs to Melastomataceae. Here, we present its complete plastome. To our knowledge, this is the first reported complete chloroplast genome of S. erythrotrichus. The complete plastome of S. erythrotrichus is 160,731 bp in length with a typical quadripartite structure, consisting of four regions: large single-copy (LSC) region (85,483 bp), small single-copy (SSC) region (17,007 bp), and two inverted repeat regions (IRs, 26,780 bp). It contains 128 genes (79 coding genes, four rRNAs, and 30 tRNAs). The overall GC content is 36.9% and in the LSC, SSC, and IR regions are 34.70%, 30.40%, and 42.50%, respectively. Our study contributes to the molecular phylogenetic studies of Scorpiothyrsus and Melastomataceae.

[Synthesis and identification of rutin complete antigen and analysis its immunogenicity].

OBJECTIVE: Synthesis and identification of complete antigen of rutin, the traditional Chinese medicine active ingredient, and develop rapid detection of rutin using enzyme-linked immunoassay method (ELISA). Immunogenicity of the complete antigen was also studied. METHOD: Prepare the complete antigen by sodium periodate solution and identified by UV scanning and SDS-PAGE test. Male New Zealand white rabbits were immunized by the antigen to obtain the antiserum. RESULT: The results of UV analysis showed that the coupling ratio of complete antigen is 13: 1. SDS-PAGE display of the artificial antigen was delayed compared with bovine serum protein. The titer of rutin antibody is 1:4 000. The sensitivity of IC50 was 5.37 mg x L(-1), the lowest detection limit was 1 mg x L(-1), the average recovery was 102%, the intra and interspecific RSD were less than 10%, cross-reactivity rate of antibodies and other analogs were less than 1%. CONCLUSION: Rutin complete antigen was synthesized successfully, and the rapid detection of rutin by ELISA method was successfully established.