Single-molecule analysis reveals rotational substeps and chemo-mechanical coupling scheme of V-ATPase.

V-ATPase (V), the catalytic domain of an ion-pumping V-ATPase, is a molecular motor that converts ATP hydrolysis-derived chemical energy into rotation. Here, using a gold nanoparticle probe, we directly observed rotation of V from the pathogen (EhV). We found that 120° steps in each ATP hydrolysis event are divided into 40 and 80° substeps.

Formation of the Cu -Phenoxyl Radical by Reaction of O with a Cu -Phenolate Complex via the Cu -Phenoxyl Radical.

Reaction of Cu(ClO ) ⋅6 H O with a tripodal 2N2O ligand, H Me NL, having a p-(dimethylamino)phenol moiety, in CH Cl /MeOH (1:1 v/v) under basic conditions under an inert gas atmosphere gave [Cu(Me NL)(H O)] (1). The same reaction carried out under aerobic conditions gave [Cu(Me NL)(MeOH)]ClO (2), which could be obtained also from the isolated complex 1 by reaction with O in CH Cl /MeOH. The X-ray crystal structures of 1 and 2 revealed similar square-pyramidal structures, but 2 showed the (dimethylamino)phenoxyl radical features.

Light-driven molecular switch for reconfigurable spin filters.

Artificial molecular switches and machines that enable the directional movements of molecular components by external stimuli have undergone rapid advances over the past several decades. Particularly, overcrowded alkene-based artificial molecular motors are highly attractive from the viewpoint of chirality switching during rotational steps. However, the integration of these molecular switches into solid-state devices is still challenging.

Heterogeneous, dynamic, and stochastic nature of mammalian spermatogenic stem cells.

Mammalian testes produce a huge number of sperm over a long period. This process, essential for the continuity of life, depends on the delicate balance of self-renewal and differentiation of resident stem cells, termed spermatogenic (spermatogonial) stem cells or SSCs. SSCs have motivated many researchers to query their identity, behavior, and regulation in the tissue microenvironment.

Imaging of Developing Metaxylem Vessel Elements in Cultured Hypocotyls.

An in vitro induction system for xylem vessel formation is a useful tool for visualizing the differentiation of xylem vessel cells. A procedure for inducing xylem vessel cell differentiation in hypocotyls of Arabidopsis thaliana is described here. Metaxylem vessel elements form ectopically in excised hypocotyl tissue following treatment with bikinin.

Control of excitatory hierarchical circuits by parvalbumin-FS basket cells in layer 5 of the frontal cortex: insights for cortical oscillations.

The cortex contains multiple neuron types with specific connectivity and functions. Recent progress has provided a better understanding of the interactions of these neuron types as well as their output organization particularly for the frontal cortex, with implications for the circuit mechanisms underlying cortical oscillations that have cognitive functions. Layer 5 pyramidal cells (PCs) in the frontal cortex comprise two major subtypes: crossed-corticostriatal (CCS) and corticopontine (CPn) cells.

Enrichment of Phosphatidylinositol 4,5-Bisphosphate in the Extra-Invasive Hyphal Membrane Promotes Colletotrichum Infection of Arabidopsis thaliana.

Pathogenic fungi from the genus Colletotrichum form invasive hyphae; the hyphae are surrounded by an extra-invasive hyphal membrane (EIHM), which is continuous with the plant plasma membrane. Although the EIHM plays a crucial role as the interface between plant and fungal cells, its precise function during Colletotrichum infection remains elusive. Here, we show that enrichment of phosphoinositides (PIs) has a crucial role in Colletotrichum infection.

Dynamic chromatin organization in the cell.

The organization and regulation of genomic DNA as nuclear chromatin is necessary for proper DNA function inside living eukaryotic cells. While this has been extensively explored, no true consensus is currently reached regarding the exact mechanism of chromatin organization. The traditional view has assumed that the DNA is packaged into a hierarchy of structures inside the nucleus based on the regular 30-nm chromatin fiber.

Dynamic chromatin organization without the 30-nm fiber.

Chromatin in eukaryotic cells is a negatively charged polymer composed of DNA, histones, and various associated proteins. Over the past ten years, our view of chromatin has shifted from a static regular structure to a dynamic and highly variable configuration. While the details are not fully understood yet, chromatin forms numerous compact domains that act as dynamic functional units of the genome in higher eukaryotes.

Single-cell quantification of the concentrations and dissociation constants of endogenous proteins.

Kinetic simulation is a useful approach for elucidating complex cell-signaling systems. The numerical simulations required for kinetic modeling in live cells critically require parameters such as protein concentrations and dissociation constants ( ). However, only a limited number of parameters have been measured experimentally in living cells.

A Rho-actin signaling pathway shapes cell wall boundaries in Arabidopsis xylem vessels.

Patterned cell wall deposition is crucial for cell shapes and functions. In Arabidopsis xylem vessels, ROP11 GTPase locally inhibits cell wall deposition through microtubule disassembly, inducing pits in cell walls. Here, we show that an additional ROP signaling pathway promotes cell wall growth at pit boundaries.

Open niche regulation of mouse spermatogenic stem cells.

In mammalian testes, robust stem cell functions ensure the continual production of sperm. In testicular seminiferous tubules, spermatogenic stem cells (SSCs) are highly motile and are interspersed between their differentiating progeny, while undergoing self-renewal and differentiation. In such an "open niche" microenvironment, some SSCs proliferate, while others exit the stem cell compartment through differentiation; therefore, self-renewal and differentiation are perfectly balanced at the population (or tissue) level, a dynamics termed "population asymmetry.

Chromatin as a nuclear spring.

The nucleus in eukaryotic cells is the site for genomic functions such as RNA transcription, DNA replication, and DNA repair/recombination. However, the nucleus is subjected to various mechanical forces associated with diverse cellular activities, including contraction, migration, and adhesion. Although it has long been assumed that the lamina structure, underlying filamentous mesh-work of the nuclear envelope, plays an important role in resisting mechanical forces, the involvement of compact chromatin in mechanical resistance has also recently been suggested.

High Order Formation and Evolution of Hornerin in Primates.

Genomic duplication or loss can accelerate evolution because the number of repeats could affect molecular pathways and phenotypes. We have previously reported that the repeated region of filaggrin (FLG), a crucial component of the outer layers of mammalian skin, had high levels of nucleotide diversity with species-specific divergence and expansion and that it evolved under the birth-and-death model. We focused on hornerin (HRNR), a member of the same gene family that harbor similar tandem repeats as FLG, and examined the formation process of repeated regions and the evolutional model that best fit the HRNR repeated region in the crab-eating macaque (Macaca fascicularis), orangutan (Pongo abelii), gorilla (Gorilla gorilla), and chimpanzee (Pan troglodytes) and compared them with the human (Homo sapiens) sequence.

Timing matters: A strategy for neurons to make diverse connections.

Neurogenesis proceeds like a continuous wave, in which each type of neurons is produced over a few days to several days. During this protracted time window, early-born and late-born neurons are sequentially produced with a considerable time lag. Even if they are identical in their genetic and molecular specifications, they could develop different characteristics under the influences of the timing of their birth.

Impact on predictability of tropical and mid-latitude cyclones by extra Arctic observations.

Recent research has demonstrated that additional winter radiosonde observations in Arctic regions enhance the predictability of mid-latitude weather extremes by reducing uncertainty in the flow of localised tropopause polar vortices. The impacts of additional Arctic observations during summer are usually confined to high latitudes and they are difficult to realize at mid-latitudes because of the limited scale of localised tropopause polar vortices. However, in certain climatic states, the jet stream can intrude remarkably into the mid-latitudes, even in summer; thus, additional Arctic observations might improve analysis validity and forecast skill for summer atmospheric circulations over the Northern Hemisphere.

Reconstruction of ROP GTPase Domains on the Plasma Membrane in Tobacco Leaves.

Rho-type small GTPases (Rho GTPases) play central roles in various cellular events. Rho GTPases are often activated locally on the plasma membrane, forming plasma membrane domains, which induce downstream signaling. We describe an experimental procedure designed for inducing the production of de novo plasma membrane domains using Arabidopsis ROP11 GTPase.

Complex Haplotypes of Gene Deletions Harbor Signatures of a Selective Sweep in East Asian Populations.

The deletion of the metabolizing Glutathione S-transferase Mu 1 () gene has been associated with multiple cancers, metabolic and autoimmune disorders, as well as drug response. It is unusually common, with allele frequency reaching up to 75% in some human populations. Such high allele frequency of a derived allele with apparent impact on an otherwise conserved gene is a rare phenomenon.

Composite regulation of ERK activity dynamics underlying tumour-specific traits in the intestine.

Acting downstream of many growth factors, extracellular signal-regulated kinase (ERK) plays a pivotal role in regulating cell proliferation and tumorigenesis, where its spatiotemporal dynamics, as well as its strength, determine cellular responses. Here, we uncover the ERK activity dynamics in intestinal epithelial cells (IECs) and their association with tumour characteristics. Intravital imaging identifies two distinct modes of ERK activity, sustained and pulse-like activity, in IECs.

Selective constraint acting on TLR2 and TLR4 genes of Japanese frogs.

Toll-like receptors (TLRs) are an important component of innate immunity, the first line of pathogen defence. One of the major roles of TLRs includes recognition of pathogen-associated molecular patterns. Amphibians are currently facing population declines and even extinction due to chytridiomycosis caused by the (Bd) fungus.

Targeted gene disruption by use of CRISPR/Cas9 ribonucleoprotein complexes in the water flea Daphnia pulex.

The microcrustacean Daphnia pulex is an important model for environmental, ecological, evolutionary and developmental genomics because its adaptive life history displays plasticity in response to environmental changes. Even though the whole-genome sequence is available and omics data have actively accumulated for this species, the available tools for analyzing gene function have thus far been limited to RNAi (RNA interference) and TALEN (the transcription activator-like effector nuclease) systems. The development of the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated 9) system is thus expected to further increase the genetic tractability of D.

Condensins under the microscope.

Condensins are key players in mitotic chromosome condensation. Using an elegant combination of state-of-the-art imaging techniques, Walther et al. (2018.

Live-cell Imaging with Genetically Encoded Protein Kinase Activity Reporters.

Protein kinases play pivotal roles in intracellular signal transduction, and dysregulation of kinases leads to pathological results such as malignant tumors. Kinase activity has hitherto been measured by biochemical methods such as in vitro phosphorylation assay and western blotting. However, these methods are less useful to explore spatial and temporal changes in kinase activity and its cell-to-cell variation.