The role of clathrin in exocytosis and the mutual regulation of endo- and exocytosis in plant cells

Within the plant endomembrane system, the vesicle coat protein clathrin localizes to the plasma membrane (PM) and the trans-Golgi Network/Early Endosome (TGN/EE). While the role of clathrin as a major component of endocytosis at the PM is well established, its function at TGN/EE, possibly in exocytosis or the vacuolar pathway, is a matter of debate. This shared function of clathrin also opens a question whether plant cells possess a homeostatic mechanisms that balance rates of opposite trafficking routes, such as endo- and exocytosis. Here we address these questions using lines inducibly silencing CLATHRIN HEAVY CHAIN (CHC). We find a relocation of exocytic soluble and integral membrane protein cargoes to the vacuole, supporting a function of clathrin in exocytosis. A comparison with lines overexpressing AUXILIN-LIKE1, where inhibition of CME precedes rerouting of secretory cargoes, does not support a homeostatic regulatory mechanism adjusting exocytosis to the rates of endocytosis. Complementary experiments reveal only minor and variably detectable reductions in the rates of CME in secretory mutants, also not indicative of a converse homeostatic mechanism adjusting rates of endocytosis to the rates of secretion.

Axes of inter-sample variability among transcriptional neighborhoods reveal disease associated cell states in single-cell data

As single-cell datasets grow in sample size, there is a critical need to characterize cell states that vary across samples and associate with sample attributes like clinical phenotypes. Current statistical approaches typically map cells to cell-type clusters and examine sample differences through that lens alone. Here we present covarying neighborhood analysis (CNA), an unbiased method to identify cell populations of interest with greater flexibility and granularity. CNA characterizes dominant axes of variation across samples by identifying groups of very small regions in transcriptional space, termed neighborhoods, that covary in abundance across samples, suggesting shared function or regulation. CNA can then rigorously test for associations between any sample-level attribute and the abundances of these covarying neighborhood groups. We show in simulation that CNA enables more powerful and accurate identification of disease-associated cell states than a cluster-based approach. When applied to published datasets, CNA captures a Notch activation signature in rheumatoid arthritis, redefines monocyte populations expanded in sepsis, and identifies a previously undiscovered T-cell population associated with progression to active tuberculosis.

diversity of Maa (Nilotic) adverbs

Maa linguistic varieties (Maasai, Parakuyo, Chamus, Samburu, among others), of the Eastern Nilotic family (Nilo-Saharan phylum), have words which can modify a predicate or predication and have the function of what cross-linguistically are called adverbs. While these words can be considered a single class due to this shared function and distribution, there are nevertheless morphosyntactic and usage distinctions. This is partly due to disparate historical origins, but also to semantics and different typical collocations. Among other distinctions, some adverbs can function as nominal tense/aspect markers within a determined nominal phrase (DP). Though the origins of all adverbs cannot be traced, the paper documents sources in oblique prepositional phrases, relational nouns, adjectives, relative clauses, and perhaps infinitive verbs, involving a wide range of lexical roots, such as ‘little’, ‘paint, mark’, ‘be abundant (with grass), be generous’, and others. Some synchronic adverbs do not have evident sources in other word classes, including the ­most frequently used word for ‘previously, before’, and the modal adverb ‘probably not, unlikely’ which is also an attenuative adverb. Maa adjectives and nouns largely overlap in their morphosyntax, but the ability to be modified by certain adverbs distinguishes them.

Rhythmic Keccak: SCA Security and Low Latency in HW

Glitches entail a great issue when securing a cryptographic implementation in hardware. Several masking schemes have been proposed in the literature that provide security even in the presence of glitches. The key property that allows this protection was introduced in threshold implementations as non-completeness. We address crucial points to ensure the right compliance of this property especially for low-latency implementations. Specifically, we first discuss the existence of a flaw in DSD 2017 implementation of Keccak by Gross et al. in violation of the non-completeness property and propose a solution. We perform a side-channel evaluation on the first-order and second-order implementations of the proposed design where no leakage is detected with up to 55 million traces. Then, we present a method to ensure a non-complete scheme of an unrolled implementation applicable to any order of security or algebraic degree of the shared function. By using this method we design a two-rounds unrolled first-order Keccak-

Shared function and moonlighting proteins in molybdenum cofactor biosynthesis

The biosynthesis of the molybdenum cofactor (Moco) is a highly conserved pathway in bacteria, archaea and eukaryotes. The molybdenum atom in Moco-containing enzymes is coordinated to the dithiolene group of a tricyclic pyranopterin monophosphate cofactor. The biosynthesis of Moco can be divided into three conserved steps, with a fourth present only in bacteria and archaea: (1) formation of cyclic pyranopterin monophosphate, (2) formation of molybdopterin (MPT), (3) insertion of molybdenum into MPT to form Mo-MPT, and (4) additional modification of Mo-MPT in bacteria with the attachment of a GMP or CMP nucleotide, forming the dinucleotide variants of Moco. While the proteins involved in the catalytic reaction of each step of Moco biosynthesis are highly conserved among the Phyla, a surprising link to other cellular pathways has been identified by recent discoveries. In particular, the pathways for FeS cluster assembly and thio-modifications of tRNA are connected to Moco biosynthesis by sharing the same protein components. Further, proteins involved in Moco biosynthesis are not only shared with other pathways, but additionally have moonlighting roles. This review gives an overview of Moco biosynthesis in bacteria and humans and highlights the shared function and moonlighting roles of the participating proteins.

Preschoolers' extension of novel words to animals and artifacts

ABSTRACTWe examined whether preschoolers' ontological knowledge would influence lexical extension. In Experiment 1, four-year-olds were presented with a novel label for either an object with eyes described as an animal, or the same object without eyes described as a tool. In the animal condition, children extended the label to similar-shaped objects, whereas in the tool condition, children extended the label to similar-function objects. In Experiment 2, when four-year-olds were presented with objects with eyes described as tools, they extended the label on the basis of shared function. These experiments suggest that preschoolers' conceptual knowledge guides their lexical extension.