Vascular plants appeared ~410 million years ago then diverged into several lineages of which only two survive: the euphyllophytes (ferns and seed plants) and the lycophytes (1). We report here the genome sequence of the lycophyte Selaginella moellendorffii (Selaginella), the first non-seed vascular plant genome reported. By comparing gene content in evolutionary diverse taxa, we found that the transition from a gametophyte- to sporophyte-dominated life cycle required far fewer new genes than the transition from a non-seed vascular to a flowering plant, while secondary metabolic genes expanded extensively and in parallel in the lycophyte and angiosperm lineages. Selaginella differs in post-transcriptional gene regulation, including small RNA regulation of repetitive elements, an absence of the tasiRNA pathway and extensive RNA editing of organellar genes.

The multipole resonance probe (MRP) was recently proposed as an economical and industry compatible plasma diagnostic device (Lapke et al 2008 Appl. Phys. Lett. 93 051502). This communication reports the experimental characterization of a first MRP prototype in an inductively coupled argon/nitrogen plasma at 10 Pa. The behavior of the device follows the predictions of both an analytical model and a numerical simulation. The obtained electron densities are in excellent agreement with the results of Langmuir probe measurements.

Despite considerable recent progress in understanding intergeneric relationships, a comprehensive analysis of Podocarpaceae at the species level using molecular data, biogeography, anatomy, and morphology has not been previously attempted. Here we present sequence analyses of rbcL, nrITS1 and NEEDLY intron 2 for two‐thirds (183 accessions of 145 taxa) of all Podocarpaceae species representing all genera except Parasitaxus. These analyses include many more species and accessions than previous studies and result in a more resolved phylogeny. The comprehensive anatomical and morphological study ensures that the identification of taxa is correct and also provides clade support. Bayesian and parsimony analyses were used to resolve 20 well‐supported monophyletic groups including 11 groups of the formerly poorly resolved subgenera Podocarpus and Foliolatus. The well‐resolved topology is supported by anatomical and morphological features and is highly congruent with geographical distribution. © The Willi Hennig Society 2011.

In flowering plants, arguably the most significant transcription factors regulating development are MADS-domain proteins, encoded by Type I and Type II MADS-box genes. Type II genes are divided into the MIKCC and MIKC* groups. In angiosperms, these types and groups play distinct roles in the development of female gametophytes, embryos, and seeds (Type I); vegetative and floral tissues in sporophytes (MIKCC); and male gametophytes (MIKC*), but their functions in other plants are largely unknown. The complete set of MADS-box genes has been described for several angiosperms and a moss, Physcomitrella patens. Our examination of the complete genome sequence of a lycophyte, Selaginella moellendorffii, revealed 19 putative MADS-box genes (13 Type I, 3 MIKCC, and 3 MIKC*). Our results suggest that the most recent common ancestor of vascular plants possessed at least two Type I and two Type II genes. None of the S. moellendorffii MIKCC genes were identified as orthologs of any floral organ identity genes. This strongly corroborates the view that the clades of floral organ identity genes originated in a common ancestor of seed plants after the lineage that led to lycophytes had branched off, and that expansion of MIKCC genes in the lineage leading to seed plants facilitated the evolution of their unique reproductive organs. The number of MIKC* genes and the ratio of MIKC* to MIKCC genes is lower in S. moellendorffii and angiosperms than in P. patens, correlated with reduction of the gametophyte in vascular plants. Our data indicate that Type I genes duplicated and diversified independently within lycophytes and seed plants. Our observations on MADS-box gene evolution echo morphological evolution since the two lineages of vascular plants appear to have arrived independently at similar body plans. Our annotation of MADS-box genes in S. moellendorffii provides the basis for functional studies to reveal the roles of this crucial gene family in basal vascular plants.

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The ancient and cosmopolitan lycophyte genus Selaginella has living representatives around the world, but their historical biogeography has not been assessed with modern methods. We estimated a time‐calibrated phylogeny using DNA marker regions rbcL and ITS1‐5.8S‐ITS2 from 200 species. Node density analyses revealed that Selaginellaceae has significantly older median and mean node ages than other putative “ancient” families. We used statistical model comparison to assess different biogeographical models on our dated tree, and to estimate ancestral ranges. These revealed that Selaginella originated on Euramerica around 383 Ma in the Devonian period, while its peak diversification began with the formation of Pangea. The divergence of the two main species‐rich Selaginella lineages occurred approximately 318 Ma on the supercontinent. The major divergences within these main lineages of Selaginella took place in the Late Permian and Early Triassic, along with lineages highly adapted for xeric habitats on Pangea.

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Throughout recent history, metabolites of microbial origin have had an extraordinary impact on the welfare of humanity. In fact, natural products have largely been –and still are– considered an exceedingly valuable platform for the discovery of new drugs against diverse pathologies. Such value is partly due to their higher complexity and chemical diversity as compared to those of synthetic and combinatorial compounds. Mutations in the Von Hippel-Lindau (vhl) gene are responsible for VHL disease, congenital polycythemia, and are found in many sporadic tumor types. The primary cause of morbidity and mortality for these patients arises from progression of Renal Cell Carcinoma (RCC) or end-stage renal disease. Inactivation of the Von Hippel-Lindau (vhl) tumor suppressor gene arises in the majority of Renal Cell Carcinoma (RCC) as well as in other types of cancer and is associated with a high degree of vascularization and poor prognosis. Loss of pVHL function thus represents a pathognomonic molecular defect for therapeutic exploitation. In this study, renal carcinoma cell lines with naturally occurring vhl mutations (RCC4 VA) and their genetically matched wild-type vhl (RCC4 VHL) counterparts were seeded onto 96-well plates and treated with a collection of 1,040 organic extracts obtained from 130 bacterial strains belonging to at least 25 genera of the phyla Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes. This strategy allowed us to identify several extracts obtained from bacterial strain F-278,770T, the type strain of the recently proposed new species Pseudomonas granadensis, showing biological activities not associated with previously known bioactive metabolites. The fractionation and structural elucidation of one of these extracts led to the discovery of a new lipodepsipeptide (MDN-0066) with specific toxicity in pVHL deficient cells that is not detectable in cells with pVHL expression rescue. This specific toxicity is associated with apoptosis induction in VHL deficient cell line as demonstrated with PARP activation and Annexin V staining. Our study demonstrated the feasibility of selectively targeting the loss of the vhl tumor suppressor gene for potential clinical benefit. Our results may have great impact on the development of new targeted therapies from natural products for the treatment of cancer and other genetic diseases.