Discordant patterns of morphological and genetic divergence in the closely related species Schizanthus hookeri and S.?grahamii (Solanaceae)

In this study I have examined the patterns of morphological and genetic differentiation between two species of the Andean genus Schizanthus that differ in their pollination and mating systems. Schizanthus hookeri has a bee pollination syndrome and is strongly dependent on pollinators for seed set. In contrast, S.?grahamii has a hummingbird pollination syndrome and exhibits late autonomous selfing. Southern populations of the latter species have red flowers (reddish morph), while northern populations have yellow (yellowish morph) or pink flowers (pinkish morph). I used two noncoding chloroplast DNA (cpDNA) regions to investigate the genetic affinities between S.?hookeri and the three morphs of S.?grahamii. I also performed intra- and interspecific crosses to assess whether gene flow between species was possible. Phylogenetic analyses supported the existence of two differentiated clades that did not match currently accepted taxonomic classification. Accordingly, genetic distance did not correlate significantly with morphological distance. No fruits were produced from interspecific crosses, and there were no individuals with intermediate morphology that could indicate current and frequent hybridization events between species.?I propose that the discordance between cpDNA data and conventional taxonomy could be explained by parallel evolution, or alternatively, by a very sporadic hybridization.     

Antiproliferative activity of withanolide derivatives from Jaborosa cabrerae and Jaborosa reflexa. Chemotaxonomic considerations

Three withanolides were isolated from the aerial parts of Jaborosa reflexa Phil. Jaborosa cabrerae Barboza yielded five sativolide withanolides (including jaborosalactones R, S, 38, and 39) and two trechonolide withanolides epimeric at C-23 (trechonolide A and jaborosalactone 32). In addition, five derivatives were obtained by chemical derivatization of jaborosalactone 38, and all compounds were fully characterized by 1D and 2D NMR spectroscopic studies. The in vitro antiproliferative activities of the major natural withanolides and the semisynthetic derivatives were examined against HBL-100, HeLa, SW1573, T-47D, and WiDr human solid tumor cancer cell lines. Some chemotaxonomic considerations are discussed.     

Analysing the Floral Elements of the Lost Tree of Easter Island: A Morphometric Comparison between the Remaining Ex-Situ Lines of the Endemic Extinct Species Sophora toromiro

Sophora toromiro (Phil) Skottsb. is a species that has been extinct in its natural habitat Easter Island (Rapa Nui) for over 50 years. However, seed collections carried out before its extinction have allowed its persistence ex-situ in different botanical gardens and private collections around the world. The progenies of these diverse collections have been classified in different lines, most of them exhibiting high similarity as corroborated by molecular markers. In spite of this resemblance observed between the different lines, one of them (Titze) has dissimilar floral elements, thus generating doubts regarding its species classification. The floral elements (wing, standard and keel) belonging to three different S. toromiro lines and two related species were analyzed using geometric morphometrics. This method was applied in order to quantify the floral shape variation of the standard, wing, and keel between the different lines and control species. Geometric morphometrics analyses were able to distinguish the floral elements at both intra (lines) and inter-specific levels. The present results are on line with the cumulative evidence that supports the Titze line as not being a proper member of the S. toromiro species, but probably a hybridization product or even another species of the Edwardsia section. The reintroduction programs of S. toromiro should consider this information when assessing the authenticity and origin of the lines that will be used to repopulate the island.     

Morphological, Chemical, and Genetic Diversity of Tropical Marine Cyanobacteria Lyngbya spp. and Symploca spp. (Oscillatoriales)

Although diverse natural products have been isolated from the benthic, filamentous cyanobacterium Lyngbya majuscula, it is unclear whether this chemical variation can be used to establish taxonomic relationships among disparate collections. We compared morphological characteristics, secondary-metabolite compositions, and partial 16S ribosomal DNA (rDNA) sequences among several collections of L. majuscula Gomont, Lyngbya spp., and Symploca spp. from Guam and the Republic of Palau. The morphological characteristics examined were cell length, cell width, and the presence or absence of a calyptra. Secondary metabolites were analyzed by two-dimensional thin-layer chromatography. Each collection possessed a distinct cellular morphology that readily distinguished Lyngbya spp. from Symploca spp. Each collection yielded a unique chemotype, but common chemical characteristics were shared among four collections of L. majuscula. A phylogeny based on secondary-metabolite composition supported the reciprocal monophyly of Lyngbya and Symploca but yielded a basal polytomy for Lyngbya. Pairwise sequence divergence among species ranged from 10 to 14% across 605 bp of 16S rDNA, while collections of L. majuscula showed 0 to 1.3% divergence. Although the phylogeny of 16S rDNA sequences strongly supported the reciprocal monophyly of Lyngbya and Symploca as well as the monophyly of Lyngbya bouillonii and L. majuscula, genetic divergence was not correlated with chemical and morphological differences. These data suggest that 16S rDNA sequence analyses do not predict chemical variability among Lyngbya species. Other mechanisms, including higher rates of evolution for biosynthetic genes, horizontal gene transfer, and interactions between different genotypes and environmental conditions, may play important roles in generating qualitative and quantitative chemical variation within and among Lyngbya species.     

Soil seed bank in and between vegetation patches in arid Patagonia,Argentina

This study was conducted at two sites, 1.5 km from 1 to another in arid Argentina (39°S, 69°W). Vegetation is distributed in patches. Four microenvironments can be identified in the soil surface of these patches, and the bare interspaces among them. Hypotheses were that (1) at any time during the sampling periods, buried (viable + damaged) seeds of the most common vegetation in the patches, Larrea divaricata Cav., Atriplex lampa Gill ex Moquin, Stipa neaei Nees ex Steudel and Leymus erianthus (Phil.) Dubcovsky, are present in the soil seed bank at all four microenvironments within any vegetation patch and its associated interspace, and (2) natural plant recruitment from the soil seed bank occurs for L. divaricata, A. lampa, S. neaei, L. erianthus, Bromus tectorum L. and Poa lanuginosa Poiret ap. Lamarck in all study microenvironments. In undisturbed field areas, 32 soil samples were periodically taken using an auger in 1999. Viable and damaged seeds contained in the soil organic matter were counted for L. divaricata, A. lampa, S. neaei, and L. erianthus. In a further study, emergence and subsequent growth of L. divaricata, A. lampa, S. neaei, L. erianthus, B. tectorum and P. lanuginosa from the soil seed bank were evaluated in the various microenvironments; permanent plots (0.04 m²) were placed on each of the two study sites using four vegetation patches and their associated interspaces per site. Results supported the first hypotheses only for L. divaricata and A. lampa. However, natural recruitment from the soil only included S. neaei and P. lanuginosa through asexual, and B. tectorum through sexual reproduction. Despite the presence of buried seeds of L. divaricata and A. lampa in microenvironment 4 during most of the sampling period, bare interspaces among vegetation patches can be naturally vegetated through sexual reproduction by B. tectorum, during years of abundant, higher than long-term, annual precipitation.     

A new and interesting site for the Calcite-encrusted desmid Oocardium stratum Naeg. in the British Isles

Oocardium stratum has been discovered growing within a protruberant mass of crystalline travertine (“cron”) developing below a small spring near Cam Gill in the Yorkshire Dales. The site is described and compared with two others, one in nearby Gordale Beck and the other at Lahage, Belgium. Although the physical and chemical characteristics of two sites (Cam Gill and Lahage) are similar, there are few algae common to both. Cam Gill cron contains the best example of Oocardium travertine so far discovered in Britain. Oocardium growth rate at the new site is about 1 mm y^-1.     

Systematics of the subfamily Haplorchiinae (Trematoda: Heterphyidae), based on nuclear ribosomal DNA genes and ITS2 region

Phylogenetic relationships of 6 species in the trematode subfamily Haplorchiinae were analyzed using small and large subunit of ribosomal DNA genes (18S rDNA and 28S rDNA) and internal transcribed spacer subunit II (ITS2) region as molecular markers. Maximum Likelihood and Bayesian inference analyses of combined rDNAs and ITS2 indicated a close relationship between the genera Haplorchis and Procerovum, while these two genera were distinct from Stellantchasmus falcatus. These phylogenetic relationships were consistent with the number of testes but not with the characters of the modification of the seminal vesicle or of the ventral sucker. Although three Haplorchis spp. were, together with Procerovum, in the same cluster, their mutual topology was incongruent between rDNA and ITS2 trees. Phylogenetic analyses using other molecular markers with more species are necessary to work out solid phylogenetic relationships among the species in this subfamily.     

Comprehensive analyses of molecular phylogeny and main alkaloids for Coptis (Ranunculaceae) species identification

The medicinal plants from the genus Coptis were widely applied in clinical treatment, but no stable and systemic methods have been established for species identification and quality evaluation. Although several analytical methods have been reported for the detection of alkaloids, so far no attempt has been made to analyze the interspecific relationships between molecular phylogeny and main alkaloids in Coptis. In this study, the phylogenetic relationships within the genus Coptis from China are resolved with high support. Coptis chinensis, Coptis deltoidea and Coptis omeiensis cluster together, and this clade (‘clade III’) is sister to Coptis teeta. Here, we provide evidences that the relationships inferred by chemical taxonomy are different to those of the present molecular phylogeny. Within clade III, C. deltoidea, C. omeiensis and C. chinensis are sister to C. teeta, while C. teeta shares more similar metabolic compounds with C. deltoidea, and C. omeiensis than with C. chinensis. Most likely, the metabolic components are mainly affected by environmental factors resulting in convergent evolution of alkaloid contents that do not reflect phylogenetic relationships.     

Roles of ATP and NADPH in formation of the fe-s cluster of spinach ferredoxin

Ferredoxin (Fd) in higher plants is encoded by a nuclear gene, synthesized in the cytoplasm as a larger precursor, and imported into the chloroplast, where it is proteolytically processed, and assembled with the [2Fe-2S] cluster. The final step in the biosynthetic pathway of Fd can be analyzed by a reconstitution system composed of isolated chloroplasts and [³⁵S]cysteine, in which [³⁵S]sulfide and iron are incorporated into Fd to build up the ³⁵S-labeled Fe-S cluster. Although a lysed chloroplast system shows obligate requirements for ATP and NADPH, in vitro chemical reconstitution of the Fe-S cluster is generally thought to be energy-independent. The present study investigated whether ATP and NADPH in the chloroplast system of spinach (Spinacia oleracea) are involved in the supply of [³⁵S]sulfide or iron, or in Fe-S cluster formation itself. [³⁵S]Sulfide was liberated from [³⁵S] cysteine in an NADPH-dependent manner, whereas ATP was not necessary for this process. This desulfhydration of [³⁵S]cysteine occurred before the formation of the ³⁵S-labeled Fe-S cluster, and the amount of radioactivity in [³⁵S]sulfide was greater than that in ³⁵S-labeled holo-Fd by a factor of more than 20. Addition of nonradioactive sulfide (Na₂S) inhibited competitively formation of the ³⁵S-labeled Fe-S cluster along with the addition of nonradioactive cysteine, indicating that some of the inorganic sulfide released from cysteine is incorporated into the Fe-S cluster of Fd. ATP hydrolysis was not involved in the production of inorganic sulfide or in the supply of iron for assembly into the Fe-S cluster. However, ATP-dependent Fe-S cluster formation was observed even in the presence of sufficient amounts of [³⁵S]sulfide and iron. These results suggest a novel type of ATP-dependent in vivo Fe-S cluster formation that is distinct from in vitro chemical reconstitution. The implications of these results for the possible mechanisms of ATP-dependent Fe-S cluster formation are discussed.     

Unravelling the names,origins and chemistry of “muthis” used for male sexual disorders in KwaZulu-Natal,South Africa

In KwaZulu-Natal, most muthis (medicinal plants) associated with male sexual disorders go under the name uBangalala. Our research shows for the first time that the major plant sources for these preparations are three plants from the genus Eriosema (E. kraussianum, E. salignum and E. cordatum) and three plants from the genus Salacia (S. rehmannii, S. leptoclada and S. kraussii). Since it is the roots that contain the desired active components, and since these roots are purchased without “above-ground appendages” (i.e. leaves and stems), it posed a real challenge to bring together the root and appropriate leaf. However, this was overcome by excursions to the places of origin of the relevant plants. An interesting outcome of this task was the finding that S. rehmannii, not normally associated with KwaZulu-Natal, is quite widespread in the Maputaland Sandveld of this province in the form of S. rehmannii (KB) and S. rehmannii (SB). Indeed, these two plants are a major source of the much sought-after muthi, uBangalala.The active chemical components in the Eriosema plants are two closely-related pyranoisoflavones. The Salacia species mentioned above are rich in triterpene quinone methides, far-removed from the pyranoisoflavones present in the Eriosema series. According to the current literature, the major quinone methide, pristimerin, is used for a variety of ailments, but the evidence that it is associated with male sexual disorders is very tenuous. This, of course, raises the question whether the quinone methides, and particularly pristimerin, have hitherto untested aphrodisiac-like properties, or whether unknown minor components in the plant are responsible for perceived (but untested) sex-related activity.     

New insights into seminal and stomatal morphology and their contribution to the taxonomy of the Old World succulent perennial Salicornioideae

Seminal and stomatal morphology of three succulent halophyte genera (Sarcocornia, Halocnemum and Arthrocnemum) around the Mediterranean basin and surroundings areas were investigated. Scanning electron microscopy (SEM) investigations showed well-different seminal coat ornamentations among the studied taxa. Both Arthrocnemum macrostachyum and Halocnemum strobilaceum do not show trichomes. Conversely, the species Sarcocornia perennis and S. fruticosa can be easily identified by the presence of long curved hairs against papillae or short conic hairs, respectively. Because most of the herbarium vouchers of Sarcocornia lack seeds, and thus the permanency of seeds on plants is quite short, an alternative vegetative character as stomata was also studied using SEM and light microscope. The detailed stomatal morphological features were analysed for the first time to infer taxonomic relationships among these perennial halophytes. Stomata are constantly paracytic for the four studied species, but two morphotypes were identified related to the level arrangement of guard cells, named as sunken and prominent stomata, respectively. Sunken stomata are found in A. macrostachyum, H. strobilaceum and S. fruticosa, whereas prominent stomata are only characteristic for S. perennis. Besides, we have found somehow relationships among the ecology of these plants based on the frequency of floodings and the observed morphology and density of stomata. Nonetheless, each observed morphotype is a stable character, without any influence of climate or environmental conditions. As a result, seminal coat ornamentation and stomata morphology are the two most reliable characteristics for discriminating Mediterranean halophytes taxa, especially related to Sarcocornia taxa.     

THE AXOSTYLE OF SACCINOBACULUS : I. Structure of the Organism and Its Microtubule Bundle

The axostyle of the flagellate Saccinobaculus is a motile ribbon composed of microtubules, cross-bridged to form interconnected rows. We find a centriole-related row of dark-staining tubules near the nucleus at the anterior end of the axostyle. Other tubule rows bind parallel to this primary row, acquire ordered relationships, and become the tubules of the axostyle proper. The number of tubule rows is constant in Saccinobaculus lata from the region near the nucleus to within a few micrometers of the posterior tip of the cell. In Saccinobaculus ambloaxostylus a few tubule rows are added to the axostyle posterior to the nucleus, giving this axostyle a leaf spring construction. The tubules of S. lata are held in rows by links with a 140 Å periodicity along the tubule axis; bridges between rows of tubules are also seen but are not apparently periodic. Each tubule in S. ambloaxostylus shows an axial periodicity of 150 Å due to pairs of arms, one of which is always part of the intrarow link. Interrow bridges in this species run either from tubule to tubule or from tubule to the free arm, but as in S. lata they do not display an obvious axial periodicity. An average unit cell is presented for the axostyle of each species, and the relation of the intertubule links to the microtubule substructure is discussed.     

Proteomic analysis on the alteration of protein expression in gills of ayu (Plecoglossus altivelis) associated with salinity change

Gill is the primary osmoregulatory organ for euryhaline fish to acclimate salinity change. The effect of salinity on gill proteome in ayu, Plecoglossus altivelis, was investigated by two-dimensional gel electrophoresis (2-DE) and matrix assisted laser desorption ionization time-of-flight tandem mass spectrometry (MALDI-TOF-MS/MS). Eight of eighteen altered proteins were successfully identified. They are involved in osmoregulation, cytoskeleton, energy metabolism, and stress response. Our results showed that vinculin, echinoderm microtubule-associated protein like protein 1, pyruvate kinase, betaine–homocysteine methyltransferase (BHMT), transaldolase, glyceraldehyde 3-phosphate dehydrogenase, and heat shock protein 70 (HSP70) were down-regulated, whereas cofilin was up-regulated when ayu transferred from fresh water (FW) to brackish water (BW). Partial cDNA sequences of BHMT, HSP70, Na⁺/K⁺ ATPase (NKA) α-subunit and 18S rRNA genes were subsequently determined and used for 2-DE data verification by real-time PCR. Gill BHMT and HSP70 mRNAs decreased significantly in BW-transferred ayu, while NKA α-subunit mRNA had no significant change. It was suggested that cell volume-regulatory response, especially the protection by the BHMT/betaine system might play an important role in ayu acclimation to salinity change.     

Chemotaxonomic characterization and chemical similarity of tribes/genera of the Solanoideae subfamily (Solanaceae) based on occurrence of withanolides

Withanolides are well established as chemotaxonomic markers in the Solanaceae. A large number of withanolides have been isolated from the subfamily Solanoideae (Solanaceae). A database of the occurrences of withanolides in Solanoideae was compiled to help characterize the chemical profile and verify the chemical similarity of the tribes/genera of this subfamily. The study revealed the importance of this group of compounds as chemotaxonomic markers, especially for Physaleae, Deprea, and Jaborosa, ratifying the importance of chemotaxonomy as a tool for elucidation of taxonomic problems, such as undefined relationships of genera that are not yet included in tribes of Solanoideae.     

Origin, diversification, and evolution of Samolus valerandi (Samolaceae, Ericales)

The almost cosmopolitan distribution of Samolus valerandi is unique in the genus Samolus L. (Samolaceae), which also includes 12–15 taxa with distributions restricted to smaller areas of the Southern Hemisphere. Recent molecular phylogenetic studies based on chloroplast and nuclear DNA sequences showed that the widespread S. valerandi and the North American S. parviflorus are both part of a strongly supported clade, together with the North American S. vagans, S. spathulatus, and S. latifolius. To better understand the origin, distribution, and diversification of S. valerandi and to clarify the relationships within this clade, we performed molecular phylogenetic analyses based on the plastid trnS-G intergenic spacer and the nuclear ribosomal ITS region. We have also sought further support for relationships by examining flower and leaf characters. On the basis of new results, we propose that S. valerandi, S. parviflorus, and S. vagans are considered as part of a widespread “species complex”, with its centre of diversity in North America. No clear vicariance patterns were found regarding the phylogeography of S. valerandi, which thus seems to have dispersed secondarily to various places around the world, possibly as a result of human activities.     

Discovery of novel (6S/12aS)-heptachpyridone capable of inhibiting thrombosis in vivo

The in vitro conversion of (1S,3S)-1-dimethoxylethyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, (1S,3S)-DCCA, in rat plasma is monitored by HPLC-FT-ICR-MS. We show that the in vitro conversion of (1S,3S)-DCCA in rat plasma for 1 h leads to forming (6S/12aS)-bisdimethoxyethylheptachpyridone, reflecting intermolecular condensation of (1S,3S)-DCCA, and the in vitro conversion of (6S/12aS)-bisdimethoxyethylheptachpyridone in rat plasma for 1 h leads to forming (6S/12aS)-heptachpyridone, reflecting hydrolysis of (6S/12aS)-bisdimethoxyethylheptachpyridone. At a dose of 1.0 μmol/kg (6S/12aS)-heptachpyridone orally inhibits venous thrombosis and arterial thrombosis in vivo. Bleeding time, clotting time and international normalized ratio show that at this dose (6S/12aS)-heptachpyridone has no bleeding risk, does not lengthen clotting time and does not change the exogenous coagulation pathway. We also show that the reactions promoted by rat plasma are easy to practice by chemical synthesis. Thus our findings build a bridge across the in vivo conversion and the application.     

Phylogenetic analysis based on 28S rRNA of Babesia spp. in ruminants in China

Molecular phylogenetic analyses are mainly based on the small ribosomal RNA subunit (18S rRNA), internal transcribed spacer regions, and other molecular markers. We compared the phylogenetic relationships of Babesia spp. using large subunit ribosomal RNA, i.e., 28S rRNA, and the united 28S + 18S rRNA sequence fragments from 11 isolates of Babesia spp. collected in China. Due to sequence length and variability, the 28S rRNA gene contained more information than the 18S rRNA gene and could be used to elucidate the phlyogenetic relationships of B. motasi, B. major, and B. bovis. Thus, 28S rRNA is another candidate marker that can be used for the phylogenetic analysis of Babesia spp. However, the united fragment (28S + 18S) analysis provided better supported phylogenetic relationships than single genes for Babesia spp. in China.     

Scientific data laundering: Chimeric mitogenomes of a sparrowhawk and a nightjar covered-up by forged phylogenies

In 2017, Gang Liu and colleagues published a paper in this journal in which they described the first mitochondrial genome of Japanese Sparrowhawk Accipiter gularis (Aves, Accipitriformes). The paper included two phylogenies (one based on full mitogenomes, the other on mitochondrial 12S/16S rRNA sequences) that placed this species among the goshawks and sparrowhawks (genus Accipiter). These phylogenies also included a previously published mitogenome of Grey Nightjar Caprimulgus indicus. Here, we show that the published mitogenome of A. gularis is a chimera of three species (a sparrowhawk, a buzzard and a dove), and that the published mitogenome of C. indicus is a chimera of two owl species. Phylogenetic re-analysis showed substantial differences from those published by Liu et al. (2017): the A. gularis sequence was placed among Streptopelia doves in the 12S/16S rRNA tree, and the C. indicus sequence was placed among Otus owls in the mitogenomic and mitochondrial 12S/16S rRNA trees. The phylogenies in Liu et al. (2017) showed several other peculiarities: (i) the inclusion of Javan Hawk-eagle Nisaetus bartelsi in the mitogenome tree (whereas no mitogenome is available of this species and no such sequence has been described in the literature), (ii) reciprocal monophyly of the genera Buteo, Leucopternis and Buteogallus (whereas multiple previous studies have shown these to be para- or polyphyletic), and (iii) the placement of Black-chested Buzzard Eagle Geranoaetus melanoleucus and Crane Hawk ‘Geranoaetus’ (=Geranospiza) caerulescens as sister species (whereas all previous studies have shown these to be distantly related). Close examination of the figures in Liu et al. (2017) revealed that both phylogenies have been manually prepared or modified. The evidence indicates that Liu et al. (2017) published phylogenies that were not based on existing data but were fabricated to reflect preconceived ideas about phylogenetic relationships. The phylogenies published by Liu et al. (2017) give the impression that the mitogenomic sequence described in their paper (A. gularis) and another one (C. indicus) described by Zhao et al. (2016) are authentic and correctly identified, whereas in reality these sequences are highly problematic chimeras. The term ‘scientific data laundering’ is proposed for the practice of hiding poor or erroneous research data with fabricated or falsified figures.