Tissue mechanics modulate morphogen signalling to induce the head organiser.

Morphogenetic movements and specification of germ layers during gastrulation are key processes that establish the vertebrate body plan. Despite substantial research into the role of tissue mechanics during gastrulation and detailed characterisation of the molecular signalling networks controlling fate determination, the interplay of mechanical cues and biochemical signals during fate specification is poorly understood. Morphogens that activate Activin/Nodal/Smad2 signalling play a key role in mesoderm induction and axial patterning.

Versatile system cores as a conceptual basis for generality in cell and developmental biology.

The discovery of general principles underlying the complexity and diversity of cellular and developmental systems is a central and long-standing aim of biology. While new technologies collect data at an ever-accelerating rate, there is growing concern that conceptual progress is not keeping pace. We contend that this is due to a paucity of conceptual frameworks that support meaningful generalizations.

Actomyosin forces in cell migration: Moving beyond cell body retraction.

In textbook illustrations of migrating cells, actomyosin contractility is typically depicted as the contraction force necessary for cell body retraction. This dogma has been transformed by the molecular clutch model, which acknowledges that actomyosin traction forces also generate and transmit biomechanical signals at the leading edge, enabling cells to sense and shape their migratory path in mechanically complex environments. To fulfill these complementary functions, the actomyosin system assembles a gradient of contractile energy along the front-rear axis of migratory cells.

Noninvasive transcranial brain stimulation in central post-stroke pain: A systematic review.

Background: The aim of this systematic review is to analyze the efficacy of noninvasive brain stimulation (NBS) in the treatment of central post-stroke pain (CPSP).

Methods: We included randomized controlled trials testing the efficacy of transcranial magnetic stimulation (TMS) or transcranial direct current stimulation versus placebo or other usual therapy in patients with CPSP. Articles in English, Portuguese, Spanish, Italian, and French were included.

Mechanically guided cell fate determination in early development.

Cell fate determination, a vital process in early development and adulthood, has been the focal point of intensive investigation over the past decades. Its importance lies in its critical role in shaping various and diverse cell types during embryonic development and beyond. Exploration of cell fate determination started with molecular and genetic investigations unveiling central signaling pathways and molecular regulatory networks.

Celebrating the centennial of the most famous experiment in embryology: Hilde Mangold, Hans Spemann and the organizer.

This Issue of Cells & Development celebrates the centennial of the Spemann-Mangold organizer experiment. This was the most famous experiment in embryology and its reverberations have greatly influenced developmental biology. This historical issue describes the impact of the discovery and is a prelude to the second volume of this Festschrift, which will consist of the proceedings of the international meeting to be held in Freiburg University, at the place where the organizer was discovered.

Competence for neural crest induction is controlled by hydrostatic pressure through Yap.

Embryonic induction is a key mechanism in development that corresponds to an interaction between a signalling and a responding tissue, causing a change in the direction of differentiation by the responding tissue. Considerable progress has been achieved in identifying inductive signals, yet how tissues control their responsiveness to these signals, known as competence, remains poorly understood. While the role of molecular signals in competence has been studied, how tissue mechanics influence competence remains unexplored.

Efficacy of Insulin Titration Driven by SMS in Improving Glycemic Control in People with Type 2 Diabetes.

Aim: To evaluate the efficacy of the self-management of insulin titration based on information received by the Short Message Service (SMS).

Methods: A case-control study including 59 subjects in each arm with 16 weeks of follow-up was performed. The inclusion criteria were: (1) Subjects with type 2 diabetes (T2D) under basal insulin treatment; (2) Suboptimal glycemic control: HbA1c ≥ 7.

Cell-matrix and cell-cell interaction mechanics in guiding migration.

Physical properties of tissue are increasingly recognised as major regulatory cues affecting cell behaviours, particularly cell migration. While these properties of the extracellular matrix have been extensively discussed, the contribution from the cellular components that make up the tissue are still poorly appreciated. In this mini-review, we will discuss two major physical components: stiffness and topology with a stronger focus on cell-cell interactions and how these can impact cell migration.

Neural crest E-cadherin loss drives cleft lip/palate by epigenetic modulation via pro-inflammatory gene-environment interaction.

Gene-environment interactions are believed to play a role in multifactorial phenotypes, although poorly described mechanistically. Cleft lip/palate (CLP), the most common craniofacial malformation, has been associated with both genetic and environmental factors, with little gene-environment interaction experimentally demonstrated. Here, we study CLP families harbouring CDH1/E-Cadherin variants with incomplete penetrance and we explore the association of pro-inflammatory conditions to CLP.

Sculpting with stiffness: rigidity as a regulator of morphogenesis.

From a physical perspective, morphogenesis of tissues results from interplay between their material properties and the mechanical forces exerted on them. The importance of mechanical forces in influencing cell behaviour is widely recognised, whereas the importance of tissue material properties in vivo, like stiffness, has only begun to receive attention in recent years. In this mini-review, we highlight key themes and concepts that have emerged related to how tissue stiffness, a fundamental material property, guides various morphogenetic processes in living organisms.

Generative models of morphogenesis in developmental biology.

Understanding the mechanism by which cells coordinate their differentiation and migration is critical to our understanding of many fundamental processes such as wound healing, disease progression, and developmental biology. Mathematical models have been an essential tool for testing and developing our understanding, such as models of cells as soft spherical particles, reaction-diffusion systems that couple cell movement to environmental factors, and multi-scale multi-physics simulations that combine bottom-up rule-based models with continuum laws. However, mathematical models can often be loosely related to data or have so many parameters that model behaviour is weakly constrained.

RanBP1 plays an essential role in directed migration of neural crest cells during development.

Collective cell migration is essential for embryonic development, tissue regeneration and repair, and has been implicated in pathological conditions such as cancer metastasis. It is, in part, directed by external cues that promote front-to-rear polarity in individual cells. However, our understanding of the pathways that underpin the directional movement of cells in response to external cues remains incomplete.

Neural crest mechanosensors: Seeing old proteins in a new light.

Mechanical forces exerted on neural crest cells control their collective migration and differentiation. This perspective discusses our current understanding of neural crest mechanotransduction during cell migration and differentiation. Additionally, we describe proteins that have mechanosensitive functions in other systems, such as mechanosensitive G-protein-coupled receptors, mechanosensitive ion channels, cell-cell adhesion, and cell-matrix-interacting proteins, and highlight that these same proteins have in the past been studied in neural crest development from a purely signaling point of view.

Self-organized collective cell behaviors as design principles for synthetic developmental biology.

Over the past two decades, molecular cell biology has graduated from a mostly analytic science to one with substantial synthetic capability. This success is built on a deep understanding of the structure and function of biomolecules and molecular mechanisms. For synthetic biology to achieve similar success at the scale of tissues and organs, an equally deep understanding of the principles of development is required.

Maternal Body Mass Index and Risk of Bronchopulmonary Dysplasia in Extremely Preterm Infants.

Objective: We evaluated the relationship between maternal body mass index (BMI) and death or bronchopulmonary dysplasia (BPD). We hypothesized that in extremely low birth weight (ELBW; BW < 1,000 g) infants, the risk of death or BPD would be greater if the maternal BMI deviated further from the ideal BMI of 24.

Study Design: ELBW infants admitted to AdventHealth Neonatal Intensive Care Unit (NICU) between calendar years 2012 and 2017 were included in this retrospective observational study.

Experiences of stigma in people with epilepsy: A meta-synthesis of qualitative evidence.

Objective: Stigma is reported to cause as much distress and effect on quality of life for individuals with epilepsy as the physical symptoms of seizures. Existing quantitative reviews have focused on describing levels of stigma in epilepsy, but no qualitative review has been undertaken despite the increasing number of relevant studies. We provide a qualitative synthesis to aid the understanding of stigma experiences in adults with epilepsy across different sociocultural contexts.

Collective durotaxis along a self-generated stiffness gradient in vivo.

Collective cell migration underlies morphogenesis, wound healing and cancer invasion. Most directed migration in vivo has been attributed to chemotaxis, whereby cells follow a chemical gradient. Cells can also follow a stiffness gradient in vitro, a process called durotaxis, but evidence for durotaxis in vivo is lacking.

An exploration of the experiences of self-disgust in people with epilepsy.

Aim: To explore the experiences of self-disgust in people with epilepsy and their understandings about this.

Design: A qualitative study informed by thematic analysis.

Method: Ten adults (out of 43 individuals initially interested in taking part, with 38 of those with levels of self-disgust categorised as high) with epilepsy and uncontrolled seizures were recruited online and participated in a telephone semi-structured interview.

The mechanosensitive channel Piezo1 cooperates with semaphorins to control neural crest migration.

Cells are permanently exposed to a multitude of different kinds of signals: however, how cells respond to simultaneous extracellular signals within a complex in vivo environment is poorly understood. Here, we studied the role of the mechanosensitive ion channel Piezo1 on the migration of the neural crest, a multipotent embryonic cell population. We identify that Piezo1 is required for the migration of Xenopus cephalic neural crest.