MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community‐led open‐source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL.

Nutrient pollution and reduced grazing each can stimulate algal blooms as shown by numerous experiments. But because experiments rarely incorporate natural variation in environmental factors and biodiversity, conditions determining the relative strength of bottom-up and top-down forcing remain unresolved. We factorially added nutrients and reduced grazing at 15 sites across the range of the marine foundation species eelgrass (Zostera marina) to quantify how top-down and bottom-up control interact with natural gradients in biodiversity and environmental forcing. Experiments confirmed modest top-down control of algae, whereas fertilisation had no general effect. Unexpectedly, grazer and algal biomass were better predicted by cross-site variation in grazer and eelgrass diversity than by global environmental gradients. Moreover, these large-scale patterns corresponded strikingly with prior small-scale experiments. Our results link global and local evidence that biodiversity and top-down control strongly influence functioning of threatened seagrass ecosystems, and suggest that biodiversity is comparably important to global change stressors.

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In the vast majority of cystic fibrosis (CF) patients, deletion of residue F508 from CFTR is the cause of disease. F508 resides in the first nucleotide binding domain (NBD1) and its absence leads to CFTR misfolding and degradation. We show here that the primary folding defect arises during synthesis, as soon as NBD1 is translated. Introduction of either the I539T or G550E suppressor mutation in NBD1 partially rescues ΔF508 CFTR to the cell surface, but only I539T repaired ΔF508 NBD1. We demonstrated rescue of folding and stability of NBD1 from full-length ΔF508 CFTR expressed in cells to isolated purified domain. The co-translational rescue of ΔF508 NBD1 misfolding in CFTR by I539T advocates this domain as the most important drug target for cystic fibrosis.

Rho-dependent terminators constitute one of two major classes of terminators in Escherichia coli. Termination at these sites requires the concerted action of RNA polymerase and rho protein. We present evidence that the efficiency of termination at these sites is governed by kinetic coupling ofthe rate oftranscription ofRNA polymerase and the rate of action of rho protein. Termination experiments in vitro indicate that termination efficiency at a rho-dependent terminator is an inverse function of the rate of elongation of RNA polymerase, and each of the mutant phenotypes can be accounted for by the altered rate of elongation of the mutant RNA polymerase. Experiments in vivo show that fast-moving mutant RNA polymerases are termination deficient, while slow-moving mutant RNA polymerases are termination proficient and can suppress the termination deficiency ofa slow-acting mutant rho protein. Because of the close coupling of rho action with RNA polymerase, small changes in the elongation rate of RNA polymerase can have very large effects on termination efflciency, providing the cell with a powerful way to modulate termination at rho-dependent terminators.Transcription termination is a regulated process that controls the activity of genes located downstream from terminators and occurs at intrinsic or rho-dependent sites in Escherichia coli (1-3). rho-dependent terminators share common features but lack a strong consensus sequence. A rho binding site is a region ofRNA rich in C residues and poor in G residues with little secondary structure (4, 5), located =100 nucleotides upstream of the multiple, closely spaced termination sites characteristic of rho-dependent terminators (6-9). rho ATPase and helicase functions activated by binding to the RNA transcript facilitate transcript release and dissociation of RNA polymerase (10, 11). rho-dependent termination sites are typically RNA polymerase pause sites in the absence of rho (6-9). We have studied the effect of RNA polymerase on termination efficiency at rho-dependent terminators.There is no biochemical evidence that RNA polymerase and rho interact structurally. rho does not bind to core RNA polymerase (12); if these proteins interact, a special conformation in the ternary complex is required for this interaction to occur. However, some RNA polymerase mutations are allele-specific suppressors of the termination defects of strains with mutant rho alleles (13-15), suggesting that the two proteins at least interact functionally.A kinetic mechanism for this functional interaction is suggested by several observations. RNA polymerase with decreased pausing because of the ri S01 mutation (16) or addition of the AQ antitermination protein (17) has an increased rate of elongation and a decreased termination efficiency at rho-dependent terminators in vitro. The RpoB8 RNA polymerase with increased pausing (18) and a reduced elongation rate because it is defective in binding purine nucleotides (19) shows increased termination at rhodependent terminators in vivo (20). The ge...