Some remarkable bryophytes from the aquatic habitats in northwestern Portugal

Cet article présente de nouvelles données sur l\u27écologie et la distribution de quatre espèces de bryophytes de la flore portugaise. Dichodontium pellucidum (Hedw.) Schimp. et Blindia acuta (Hedw.) Bruch &amp; Schimp. sont récoltées pour la première fois au Portugal, la présence de Jungermannia obovata Nees est récemment confirmée dans deux localités. De plus, une mousse considérée disparue au Portugal, Climacium dendroides (Hedw.) F. Weber &amp; D. Mohr, répertoriée il y a environ 140 ans, est confirmée.This paper presents information on the ecology and distribution of four species of Portuguese bryophyte flora. Dichodontium pellucidum (Hedw.) Schimp. and Blindia acuta (Hedw.) Bruch &amp; Schimp. are recorded for the first time in Portugal. Jungermannia obovata Nees, is confirmed in two recently found localities, and Climacium dendroides (Hedw.) F. Weber &amp; D. Mohr, a moss whose last records in the same area date 140 years, and which is currently considered to be extinct in Portugal, is confirmed.</p

Analyses of charophyte chloroplast genomes help characterize theancestral chloroplastgenomeof land plants

Despite the significance of the relationships between embryophytes and their charophyte algal ancestors in deciphering the origin and evolutionary success of land plants, few chloroplast genomes of the charophyte algae have been reconstructed to date. Here, we present new data for three chloroplast genomes of the freshwater charophytes Klebsormidium flaccidum (Klebsormidiophyceae), Mesotaenium endlicherianum (Zygnematophyceae), and Roya anglica (Zygnematophyceae). The chloroplast genome of Klebsormidium has a quadripartite organization with exceptionally large inverted repeat (IR) regions and, uniquely among streptophytes, has lost the rrn5 and rrn4.5 genes from the ribosomal RNA (rRNA) gene cluster operon. The chloroplast genome of Roya differs from other zygnematophycean chloroplasts, including the newly sequenced Mesotaenium, by having a quadripartite structure that is typical of other streptophytes. On the basis of the improbability of the novel gain of IR regions, we infer that the quadripartite structure has likely been lost independently in at least three zygnematophycean lineages, although the absence of the usual rRNA operonic synteny in the IR regions of Roya may indicate their de novo origin. Significantly, all zygnematophycean chloroplast genomes have undergone substantial genomic rearrangement, which may be the result of ancient retroelement activity evidenced by the presence of integrase-like and reverse transcriptase-like elements in the Roya chloroplast genome. Our results corroborate the close phylogenetic relationship between Zygnematophyceae and land plants and identify 89 protein-coding genes and 22 introns present in the chloroplast genome at the time of the evolutionary transition of plants to land, all of which can be found in the chloroplast genomes of extant charophytes

Structure and Affinity of Two Bicyclic Glutamate Analogues at AMPA and Kainate Receptors

Ionotropic glutamate receptors (iGluRs) are involved in most of the fast excitatory synaptic transmission in the central nervous system. These receptors are important for learning and memory formation, but are also involved in the development of diseases such as Alzheimer’s disease, epilepsy and depression. To understand the function of different types of iGluRs, selective agonists are invaluable as pharmacological tool compounds. Here, we report binding affinities of two bicyclic, conformationally restricted analogues of glutamate (CIP-AS and LM-12b) at AMPA (GluA2 and GluA3) and kainate receptor subunits (GluK1–3 and GluK5). Both CIP-AS and LM-12b were found to be GluK3-preferring agonists, with <i>K</i>_i of 6 and 22 nM, respectively, at recombinant GluK3 receptors. The detailed binding mode of CIP-AS and LM-12b in the ligand-binding domains of the AMPA receptor subunit GluA2 (GluA2-LBD) and the kainate receptor subunits GluK1 (GluK1-LBD) and GluK3 (GluK3-LBD) was investigated by X-ray crystallography. CIP-AS stabilized all three receptor constructs in conformations similar to those with kainate. Remarkably, whereas LM-12b bound in a similar manner to CIP-AS in GluA2-LBD and GluK3-LBD, it introduced full closure of the ligand-binding domain in GluK1-LBD and formation of a D1-D2 interlobe hydrogen bond between Glu441 and Ser721, as also observed with glutamate. As the binding affinity of LM-12b at GluK1 is ∼8-fold better than that for CIP-AS (<i>K</i>_i of 85 and 656 nM, respectively), it shows that small changes in agonist structure can lead to prominent differences in structure and function

A miniature world in decline: European Red List of Mosses, Liverworts and Hornworts

This publication has been prepared by IUCN (International Union for Conservation of Nature) as a deliverable of the LIFE European Red Lists project (LIFE14 PRE BE 001). A miniature world in decline: The European Red List of Mosses, Liverworts and Hornworts is, therefore, a part of a series of publications released since 2015, when the project began, that also include: • European Red List of Lycopods and Ferns, 2017 • European Red List of Saproxylic Beetles, 2018 • European Red list of Terrestrial Molluscs: slugs, snails, and semi-slugs, 2019 • European Red list of Trees, 2019 • European Red list of Selected Endemic Shrubs, 2019 Based on other European Red List assessments, 59% of freshwater molluscs, 40% of freshwater fishes, 28% of grasshoppers, crickets and bush-crickets, 23% of amphibians, 20% of reptiles, 20% of ferns and lycopods, 17% of mammals, 16% of dragonflies, 13% of birds, 9% of butterflies and bees, 8% of aquatic plants and 2% of medicinal plants are threatened at the European level (Allen et al., 2014; IUCN, 2015; Hochkirch et al., 2016; García Criado et al., 2017). Additional European Red Lists assessing a selection of species showed that 22% of terrestrial molluscs, 16% of crop wild relatives and 18% of saproxylic beetles are also threatened (Cuttelod et al., 2011; Bilz et al., 2011; Cálix et al., 2018). The findings of this work suggest that 23% of bryophytes are threatened species in Europe, representing the fifth most threatened group of plants assessed so far