Butylated Hydroxytoluene (BHT) Inhibits PIN1 Exocytosis From BFA Compartments in Arabidopsis Roots.

The activity of polarly localized PIN-FORMED (PIN) auxin efflux carriers contributes to the formation of auxin gradients which guide plant growth, development, and tropic responses. Both the localization and abundance of PIN proteins in the plasma membrane depend on the regulation of PIN trafficking through endocytosis and exocytosis and are influenced by many external and internal stimuli, such as reactive oxygen species, auxin transport inhibitors, flavonoids and plant hormones. Here, we investigated the regulation of endosomal PIN cycling by using a Brefeldin A (BFA) assay to study the effect of a phenolic antioxidant ionol, butylated hydroxytoluene (BHT), on the endocytosis and exocytosis of PIN1 and PIN2.

Species-Specific Recognition of Mediated by UV-Inducible Pili and S-Layer Glycosylation Patterns.

The UV-inducible pili system of (Ups) mediates the formation of species-specific cellular aggregates. Within these aggregates, cells exchange DNA to repair DNA double-strand breaks via homologous recombination. Substitution of the pilin subunits UpsA and UpsB with their homologs from showed that these subunits facilitate species-specific aggregation.

Defining the Substrate Spectrum of the TIM22 Complex Identifies Pyruvate Carrier Subunits as Unconventional Cargos.

In mitochondria, the carrier translocase (TIM22 complex) facilitates membrane insertion of multi-spanning proteins with internal targeting signals into the inner membrane [1-3]. Tom70, a subunit of TOM complex, represents the major receptor for these precursors [2, 4-6]. After transport across the outer membrane, the hydrophobic carriers engage with the small TIM protein complex composed of Tim9 and Tim10 for transport across the intermembrane space (IMS) toward the TIM22 complex [7-12].

Sound localization in barn owls studied with manipulated head-related transfer functions: beyond broadband interaural time and level differences.

Interaural time and level differences are important cues for sound localization. We wondered whether the broadband information contained in these two cues could fully explain the behavior of barn owls and responses of midbrain neurons in these birds. To tackle this problem, we developed a novel approach based on head-related transfer functions.

Homologue replacement in the import motor of the mitochondrial inner membrane of trypanosomes.

Many mitochondrial proteins contain N-terminal presequences that direct them to the organelle. The main driving force for their translocation across the inner membrane is provided by the presequence translocase-associated motor (PAM) which contains the J-protein Pam18. Here, we show that in the PAM of the function of Pam18 has been replaced by the non-orthologous euglenozoan-specific J-protein TbPam27.

COA6 Facilitates Cytochrome c Oxidase Biogenesis as Thiol-reductase for Copper Metallochaperones in Mitochondria.

The mitochondrial cytochrome c oxidase, the terminal enzyme of the respiratory chain, contains heme and copper centers for electron transfer. The conserved COX2 subunit contains the Cu site, a binuclear copper center. The copper chaperones SCO1, SCO2, and COA6, are required for Cu center formation.

PCH1 and PCHL Directly Interact with PIF1, Promote Its Degradation, and Inhibit Its Transcriptional Function during Photomorphogenesis.

PHOTOPERIODIC CONTROL OF HYPOCOTYL 1 (PCH1) and PCH1-LIKE (PCHL) were shown to directly bind to phytochrome B (phyB) and suppress phyB thermal reversion, resulting in plants with dramatically enhanced light sensitivity. Here, we show that PCH1 and PCHL also positively regulate various light responses, including seed germination, hypocotyl gravitropism, and chlorophyll biosynthesis, by physically interacting with PHYTOCHROME INTERACTING FACTOR 1 (PIF1) and CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1). PCH1 and PCHL interact with PIF1 both in the dark and light, and regulate PIF1 abundance.

Uncoiling springs promote mechanical functionality of spider cribellate silk.

Composites, both natural and synthetic, achieve novel functionality by combining two or more constituent materials. For example, the earliest adhesive silk in spider webs - cribellate silk - is composed of stiff axial fibers and coiled fibers surrounded by hundreds of sticky cribellate nanofibrils. Yet, little is known of how fiber types interact to enable capture of insect prey with cribellate silk.

Settling for Less: Do Statoliths Modulate Gravity Perception?

Plants orientate their growth either towards (in roots) or away from (in shoots) the Earth's gravitational field. While we are now starting to understand the molecular architecture of these gravity response pathways, the gravity receptor remains elusive. This perspective looks at the biology of statoliths and suggests it is conceivable that their immediate environment may be tuned to modulate the strength of the gravity response.

Author Correction: Split intein-mediated selection of cells containing two plasmids using a single antibiotic.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Identification of a C2-symmetric diol based human immunodeficiency virus protease inhibitor targeting Zika virus NS2B-NS3 protease.

Zika virus (ZIKV) is an emerging mosquito-borne flavivirus and infection by ZIKV Asian lineage is known to cause fetal brain anomalies and Guillain-Barrés syndrome. The WHO declared ZIKV a global public health emergency in 2016. However, currently neither vaccines nor antiviral prophylaxis/treatments are available.

The structure of the periplasmic FlaG-FlaF complex and its essential role for archaellar swimming motility.

Motility structures are vital in all three domains of life. In Archaea, motility is mediated by the archaellum, a rotating type IV pilus-like structure that is a unique nanomachine for swimming motility in nature. Whereas periplasmic FlaF binds the surface layer (S-layer), the structure, assembly and roles of other periplasmic components remain enigmatic, limiting our knowledge of the archaellum's functional interactions.

Thermal Reversion of Plant Phytochromes.

Phytochromes are red/far-red reversible photoreceptors essential for plant growth and development. Phytochrome signaling is mediated by the physiologically active far-red-absorbing Pfr form that can be inactivated to the red-absorbing Pr ground state by light-dependent photoconversion or by light-independent thermal reversion, also termed dark reversion. Although the term "dark reversion" is justified by historical reasons and frequently used in the literature, "thermal reversion" more appropriately describes the process of light-independent but temperature-regulated Pfr relaxation that not only occurs in darkness but also in light and is used throughout the review.

3D Analysis of Mitosis Distribution Pattern in the Plant Root Tip with iRoCS Toolbox.

The protocol allows to define and characterize mitosis distribution patterns in the plant root meristem. The method does not require genetic markers, which makes it applicable to plants of different non-transgenic genotypes, including ecotypes, mutants, and non-model plant species. Computer analysis of the mitosis distribution in three dimensions with iRoCS Toolbox identifies statistically significant changes in proliferation activity within specific root tissues and cell lineages.

Architecture and modular assembly of S-layers revealed by electron cryotomography.

Surface protein layers (S-layers) often form the only structural component of the archaeal cell wall and are therefore important for cell survival. S-layers have a plethora of cellular functions including maintenance of cell shape, osmotic, and mechanical stability, the formation of a semipermeable protective barrier around the cell, and cell-cell interaction, as well as surface adhesion. Despite the central importance of S-layers for archaeal life, their 3-dimensional (3D) architecture is still poorly understood.

Small behavioral adaptations enable more effective prey capture by producing 3D-structured spider threads.

Spiders are known for producing specialized fibers. The radial orb-web, for example, contains tough silk used for the web frame and the capture spiral consists of elastic silk, able to stretch when prey impacts the web. In concert, silk proteins and web geometry affects the spider's ability to capture prey.

Optogenetic Repressors of Gene Expression in Yeasts Using Light-Controlled Nuclear Localization.

Introduction: Controlling gene expression is a fundamental goal of basic and synthetic biology because it allows insight into cellular function and control of cellular activity. We explored the possibility of generating an optogenetic repressor of gene expression in the model organism by using light to control the nuclear localization of nuclease-dead Cas9, dCas9.

Methods: The dCas9 protein acts as a repressor for a gene of interest when localized to the nucleus in the presence of an appropriate guide RNA (sgRNA).

FHY1 and FHY1-LIKE Are Not Required for Phytochrome A Signal Transduction in the Nucleus.

Photoreceptors of the phytochrome family control a multitude of responses in plants. Phytochrome A (phyA) is essential for far-red light perception, which is important for germination and seedling establishment in strong canopy shade. Translocation of phyA from the cytosol into nucleus is a key step in far-red light signaling and requires FAR-RED ELONGATED HYPOCOTYL 1 (FHY1) and FHY1-LIKE (FHL).

Noncompetitive binding of PpiD and YidC to the SecYEG translocon expands the global view on the SecYEG interactome in .

The SecYEG translocon constitutes the major protein transport channel in bacteria and transfers an enormous variety of different secretory and inner-membrane proteins. The minimal core of the SecYEG translocon consists of three inner-membrane proteins, SecY, SecE, and SecG, which, together with appropriate targeting factors, are sufficient for protein transport However, the SecYEG translocon has been shown to associate with multiple partner proteins, likely allowing the SecYEG translocon to process its diverse substrates. To obtain a global view on SecYEG plasticity in , here we performed a quantitative interaction proteomic analysis, which identified several known SecYEG-interacting proteins, verified the interaction of SecYEG with quality-control proteins, and revealed several previously unknown putative SecYEG-interacting proteins.

Split intein-mediated selection of cells containing two plasmids using a single antibiotic.

To build or dissect complex pathways in bacteria and mammalian cells, it is often necessary to recur to at least two plasmids, for instance harboring orthogonal inducible promoters. Here we present SiMPl, a method based on rationally designed split enzymes and intein-mediated protein trans-splicing, allowing the selection of cells carrying two plasmids with a single antibiotic. We show that, compared to the traditional method based on two antibiotics, SiMPl increases the production of the antimicrobial non-ribosomal peptide indigoidine and the non-proteinogenic aromatic amino acid para-amino-L-phenylalanine from bacteria.

odMLtables: A User-Friendly Approach for Managing Metadata of Neurophysiological Experiments.

An essential aspect of scientific reproducibility is a coherent and complete acquisition of metadata along with the actual data of an experiment. The high degree of complexity and heterogeneity of neuroscience experiments requires a rigorous management of the associated metadata. The odML framework represents a solution to organize and store complex metadata digitally in a hierarchical format that is both human and machine readable.

Differential phosphorylation of the N-terminal extension regulates phytochrome B signaling.

Phytochrome B (phyB) is an excellent light quality and quantity sensor that can detect subtle changes in the light environment. The relative amounts of the biologically active photoreceptor (phyB Pfr) are determined by the light conditions and light independent thermal relaxation of Pfr into the inactive phyB Pr, termed thermal reversion. Little is known about the regulation of thermal reversion and how it affects plants' light sensitivity.

Dissecting the plant exocyst.

The exocyst is an evolutionary conserved complex that mediates tethering of post-Golgi vesicles derived from the conventional secretory pathway to the plasma membrane (PM), before SNARE-mediated fusion. Through its tethering function, connecting secretory vesicles to the PM, it mediates spatiotemporal regulation of exocytosis. As an integral element of the secretory machinery, the exocyst has been implicated in a large variety of processes.

Effect of the baseline Y93H resistance-associated substitution in HCV genotype 3 for direct-acting antiviral treatment: real-life experience from a multicenter study in Sweden and Norway.

The NS5A resistance-associated substitution (RAS) Y93H is found quite frequently (5-10%) at baseline in direct-acting antiviral agents (DAA) treatment-naïve genotype (GT) 3a patients when studied by the population-sequencing method (cut-off 20%). This RAS may impair HCV DAA treatment response, since it possesses a high fold resistance to daclatasvir (DCV) and velpatasvir (VEL) in GT 3. We investigated the effect of baseline Y93H in patients with GT 3a infection on treatment outcome, with or without resistance-based DAA-treatment during 2014-2017.