Molecular organization of the distal tip of vertebrate motile cilia.

The beating of cilia on multi-ciliated cells (MCCs) is essential for normal development and homeostasis in animals. Unlike basal bodies or axonemes, the distal tips of MCC cilia remain poorly defined. Here, we characterize the molecular organization of the distal tip of vertebrate MCC cilia, revealing two distinct domains occupied by distinct protein constituents.

An amino acid-resolution interactome for motile cilia identifies the structure and function of ciliopathy protein complexes.

Motile cilia are ancient, evolutionarily conserved organelles whose dysfunction underlies motile ciliopathies, a broad class of human diseases. Motile cilia contain a myriad of different proteins that assemble into an array of distinct machines, and understanding the interactions and functional hierarchies among them presents an important challenge. Here, we defined the protein interactome of motile axonemes using cross-linking mass spectrometry in Tetrahymena thermophila.

The human ciliopathy protein RSG1 links the CPLANE complex to transition zone architecture.

Cilia are essential organelles and variants in genes governing ciliary function result in ciliopathic diseases. The Ciliogenesis and PLANar polarity Effectors (CPLANE) protein complex is essential for ciliogenesis in animals models but remains poorly defined. Notably, all but one subunit of the CPLANE complex have been implicated in human ciliopathy.

Emergence of cellular nematic order is a conserved feature of gastrulation in animal embryos.

Cells undergo dramatic changes in morphology during embryogenesis, yet how these changes affect the formation of ordered tissues remains elusive. Here we find that the emergence of a nematic liquid crystal phase occurs in cells during gastrulation in the development of embryos of fish, frogs, and fruit flies. Moreover, the spatial correlations in all three organisms are long-ranged and follow a similar power-law decay with less than unity for the nematic order parameter, suggesting a common underlying physical mechanism unifies events in these distantly related species.

Measuring food access using least-cost diets: Results for global monitoring and targeting of interventions to improve food security, nutrition and health.

Benchmark diets using the most affordable locally available items to meet health and nutrition needs have long been used to guide food choice and nutrition assistance. This paper describes the result of recent innovations scaling up the use of such least-cost diets by UN agencies, the World Bank, and national governments for a different purpose, which is monitoring food environments and targeting systemic interventions to improve a population's access to sufficient food for an active and healthy life. Measuring food access using least-cost diets allows a clearer understanding of where poor diets are caused by unavailability or high prices for even the lowest-cost healthy foods, insufficient income or other resources to acquire those foods, or the use of other foods instead due to reasons such as time use and meal preparation costs, or cultural factors such as taste and aspirations.

An expert panel on the adequacy of safety data and physiological roles of dietary bovine osteopontin in infancy.

Human milk, due to its unique composition, is the optimal standard for infant nutrition. Osteopontin (OPN) is abundant in human milk but not bovine milk. The addition of bovine milk osteopontin (bmOPN) to formula may replicate OPN's concentration and function in human milk.

Motor protein Kif6 regulates cilia motility and polarity in brain ependymal cells.

Motile cilia on ependymal cells that line brain ventricular walls beat in concert to generate a flow of laminar cerebrospinal fluid (CSF). Dyneins and kinesins are ATPase microtubule motor proteins that promote the rhythmic beating of cilia axonemes. Despite common consensus about the importance of axonemal dynein motor proteins, little is known about how kinesin motors contribute to cilia motility.

Conserved chromatin and repetitive patterns reveal slow genome evolution in frogs.

Frogs are an ecologically diverse and phylogenetically ancient group of anuran amphibians that include important vertebrate cell and developmental model systems, notably the genus Xenopus. Here we report a high-quality reference genome sequence for the western clawed frog, Xenopus tropicalis, along with draft chromosome-scale sequences of three distantly related emerging model frog species, Eleutherodactylus coqui, Engystomops pustulosus, and Hymenochirus boettgeri. Frog chromosomes have remained remarkably stable since the Mesozoic Era, with limited Robertsonian (i.

PCP and Septins govern the polarized organization of the actin cytoskeleton during convergent extension.

Convergent extension (CE) requires the coordinated action of the planar cell polarity (PCP) proteins and the actin cytoskeleton, but this relationship remains incompletely understood. For example, PCP signaling orients actomyosin contractions, yet actomyosin is also required for the polarized localization of PCP proteins. Moreover, the actin-regulating Septins play key roles in actin organization and are implicated in PCP and CE in frogs, mice, and fish but execute only a subset of PCP-dependent cell behaviors.

Label-free proteomic comparison reveals ciliary and nonciliary phenotypes of IFT-A mutants.

DIFFRAC is a powerful method for systematically comparing proteome content and organization between samples in a high-throughput manner. By subjecting control and experimental protein extracts to native chromatography and quantifying the contents of each fraction using mass spectrometry, it enables the quantitative detection of alterations to protein complexes and abundances. Here, we applied DIFFRAC to investigate the consequences of genetic loss of Ift122, a subunit of the intraflagellar transport-A (IFT-A) protein complex that plays a vital role in the formation and function of cilia and flagella, on the proteome of .

New tools reveal PCP-dependent polarized mechanics in the cortex and cytoplasm of single cells during convergent extension.

Unlabelled: Understanding biomechanics of biological systems is crucial for unraveling complex processes like tissue morphogenesis. However, current methods for studying cellular mechanics are limited by the need for specialized equipment and often provide limited spatiotemporal resolution. Here we introduce two new techniques, Tension by Transverse Fluctuation (TFlux) and microrheology, that overcome these limitations.

Hedgehog signaling is required for endometrial remodeling and myometrial homeostasis in the cycling mouse uterus.

Decades of work demonstrate that the mammalian estrous cycle is controlled by cycling steroid hormones. However, the signaling mechanisms that act downstream, linking hormonal action to the physical remodeling of the cycling uterus, remain unclear. To address this issue, we analyzed gene expression at all stages of the mouse estrous cycle.

An amino acid-resolution interactome for motile cilia illuminates the structure and function of ciliopathy protein complexes.

Motile cilia are ancient, evolutionarily conserved organelles whose dysfunction underlies motile ciliopathies, a broad class of human diseases. Motile cilia contain myriad different proteins that assemble into an array of distinct machines, so understanding the interactions and functional hierarchies among them presents an important challenge. Here, we defined the protein interactome of motile axonemes using cross-linking mass spectrometry (XL/MS) in .

COVID-19 mobility restrictions and stay-at-home behaviour in 2020 were associated with higher retail food prices worldwide.

COVID-19 policy responses have included mobility restrictions, and many people have chosen to stay at home to avoid exposure. These actions have ambiguous impacts on food prices, lowering demand for food away from home and perishables, while increasing supply costs for items where workers are most affected by the pandemic. We use evidence from 160 countries to identify the net direction and magnitude of association between countries' real cost of all food and mobility restriction stringency.

Perspective: Assuring the Quality of Protein in Infant Formula.

Current regulations require that the assessment of protein quality in infant formula be determined using the protein efficiency ratio (PER) rat bioassay where the growth of rats fed a test protein is compared with the growth of rats fed casein. This review cites authoritative body opinions that the PER is not a preferred method for scoring protein quality, particularly as applied to the infant formula. Methodological recommendations specified by FDA and recent guidance propose to control nonprotein dietary variables in the PER.

The RhoGEF protein Plekhg5 regulates medioapical and junctional actomyosin dynamics of apical constriction during gastrulation.

Apical constriction results in apical surface reduction in epithelial cells and is a widely used mechanism for epithelial morphogenesis. Both medioapical and junctional actomyosin remodeling are involved in apical constriction, but the deployment of medial versus junctional actomyosin and their genetic regulation in vertebrate embryonic development have not been fully described. In this study, we investigate actomyosin dynamics and their regulation by the RhoGEF protein Plekhg5 in bottle cells.

Label-free proteomic comparison reveals ciliary and non-ciliary phenotypes of IFT-A mutants.

DIFFRAC is a powerful method for systematically comparing proteome content and organization between samples in a high-throughput manner. By subjecting control and experimental protein extracts to native chromatography and quantifying the contents of each fraction using mass spectrometry, it enables the quantitative detection of alterations to protein complexes and abundances. Here, we applied DIFFRAC to investigate the consequences of genetic loss of Ift122, a subunit of the intraflagellar transport-A (IFT-A) protein complex that plays a vital role in the formation and function of cilia and flagella, on the proteome of .