NIHRDataInsights/HRCSData huggingface dataset:
Title: Molecular mechanisms determining the polarised synaptic distribution and molecular function of the retrograde endocannabinoid signalling system
Funder: Wellcome Trust

Abstract: The endocannabinoid system (ECS) acts as a negative feedback mechanism to suppress excitatory and inhibitory synaptic transmission. This is critically important for a wide range of brain functions including appetite, pain, and cognition. Moreover, ECS dysfunction is implicated in multiple neuropathologies, and there is increasing scientific and public interest in drugs that target the ECS, including medical marijuana. The molecular organisation of the ECS is highly unusual because, in reverse to other neurotransmitter systems, endocannabinoids are released from the postsynaptic membrane to activate receptors at the presynaptic membrane. Despite its importance, remarkably little is known about how the enzymes and receptors essential for ECS ‘backwards’ transmission are targeted to, and retained at, opposing sides of the synapse. Focusing on the primary cannabinoid receptor CB1R and the major endocannabinoid synthesising enzyme diacylglycerol lipase &alpha; (DAGL&alpha;) as prototypic examples, we will investigate the protein interactions and pathways that determine the architecture and organisation of the ECS. Our goal is to define how the differentially polarised trafficking of ECS components to synapses is orchestrated. This mechanistic knowledge of the ECS will advance understanding of neuronal protein polarisation and inform the design of future strategies to modulate ECS signalling for therapeutic benefit.

Lay abstract: Cannabis has been used as a medicine for thousands of years. Chemicals in cannabis work by activating a protein in the brain called cannabinoid receptor 1 (CB1R), which is part of a network of proteins called the endocannabinoid signalling system (ECS). The ECS dampens-down brain activity by reducing the amount of neurotransmitter released at connections between nerve cells called synapses. This is a vitally important feedback loop that prevents synaptic activity from spiralling out of control. We want to explore the biochemical 'nuts and bolts' of the cellular machinery that controls proteins critical for ECS function. This will provide important new information on how the ECS works, and how it can go wrong. Because a major role of the ECS is to prevent excessive activity which can kill nerve cells, our findings could eventually lead to new ways of enhancing ECS signalling to protect nerve cells in conditions like epilepsy.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Hypothalamic development from self-organising progenitors
Funder: Wellcome Trust

Abstract: The hypothalamus governs homeostasis of core body function throughout life but its development remains enigmatic. Our recent unpublished work reveals that a small region at the ventral midline of the embryonic neural tube intrinsically develops into the three classically defined domains of the adult basal hypothalamus, including a domain that contains stem cells. This suggests an unprecedented mechanism of self-organisation exists within ventral midline hypothalamic progenitor cells that we will define in this application. Our objectives are to: 1. Identify when self-organising hypothalamic progenitors are induced, and the tissues required 2. Determine the minimum cell number that can self-organise into the hypothalamus 3. Understand if self-organisation involves a self-renewing multipotent stem cell 4. Characterise cell behaviour in self-organising hypothalamic progenitor cells 5. Understand the molecular basis of hypothalamic self-organisation These studies will reveal mechanisms that orchestrate hypothalamic development. They will provide insight into the extent to which hypothalamic stem/progenitor cells can adapt over time and generate/regenerate new cell types. Finally, they may provide insight into the construction of hypothalamic organoids, an important future tool to understand the function and sensitivity of this small, intricate and hard-to-access region of the brain.

Lay abstract: The hypothalamus of the brain is critical to life, controlling growth, metabolism and reproduction, but we understand little about its development. We have recently made the unexpected breakthrough that a small region of the early embryo can grow into the three domains that classically define the adult hypothalamus. Here we want to understand how this embryonic region forms and decipher the information it contains that is the blueprint for hypothalamic construction. Intriguingly, the embryonic cells bear resemblance to adult hypothalamic stem cells that can generate new neurons through life, supporting adaptation. We will investigate if these hypothalamic stem cells are made in the early embryo. In the long-term our studies could let us build the hypothalamus in a dish, an important future goal in medicine for making personalised cells and restoring the damaged brain.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Molecular basis of phase separation in viral replication and neurodegenerative disease
Funder: Wellcome Trust

Abstract: Membrane-less organelles (MLOs) are multicomponent structures that form by liquid-liquid phase separation (LLPS) of proteins/RNA. They play key roles in organising cells, signalling, stress and viral factory formation, whilst aberrant LLPS is associated with several neurodegenerative diseases (e.g. MND). MLOs are heterogeneous and dynamic, making it challenging to elucidate their composition, structure and biogenesis. New tools are urgently needed to study LLPS in vitro and in vivo to address fundamental questions of the molecular mechanism of LLPS, and to unravel how it contributes to homeostasis and disease. Here, I will develop a toolkit of MS-based methods to study LLPS, focussing on two systems: TDP-43, implicated in MND, and NSP2/NSP5, involved in Rotavirus viral factory formation. This will reveal new insights into the structure/dynamics of these proteins (which promote/suppress LLPS) and the protein-protein/RNA interactions which nucleate LLPS. I will study LLPS in vivo using, and developing, structural MS methods to reveal the proteins recruited into MLOs and the interactions mediating recruitment. This toolkit of MS methods, reinforced with biochemical/cellular/functional assays, will afford new mechanistic insights into two important systems, uncover new targets to combat neurodegeneration and viral infection, and open the door to revealing how LLPS controls many other cellular processes.

Lay abstract: Cells are organised into compartments, including membrane-bound organelles, e.g. nucleus/mitochondria, or membrane-less organelles, formed form by phase separation (akin to oily droplets that form in water). In certain neurodegenerative diseases, such as motor neuron disease and dementia, proteins normally found in membrane-less organelles form toxic deposits. Also, when viruses invade cells, membrane-less organelles form where viral replication occurs. Despite the importance of membrane-less organelles in disease and infection, we still don’t understand how they form. I will make new discoveries about the structures of the proteins that form membrane-less organelles by studying a model protein, TDP-43, which plays a role in in neurodegeneration, and proteins that form viral replication organelles in Rotavirus-infected cells. Rotaviruses, a common cause of gastrointestinal infections, are responsible for more than 200,000 child deaths annually. The understanding of membrane-less organelle formation afforded by these studies may lead to new treatments for neurodegenerative disease and viral infection.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Molecular mechanisms of slow axonal transport
Funder: Wellcome Trust

Abstract: Neuronal axons can be a metre long and are maintained for a lifetime, making them acutely vulnerable to defects in microtubule mediated long distance transport. There are two broad categories of axonal transport in neurons, fast and slow. Slow axonal transport carries at least three times the material of fast transport, but ten to a hundred times more slowly. Protein moved by slow transport can be months old in the distal axon, and this process slows further with aging. Despite dysfunctional axonal transport being common in neurodegeneration, where aging is the major risk factor for disease, the mechanisms that regulate slow transport are very poorly characterised. Critically, whether transport time directly affects the accumulated damage and function of its protein cargo is unknown. The aim of this project is to understand how slow transport is regulated, whether transit time can influence the half-life and function of proteins, and further - whether it’s possible to reverse age-related decline in transport. To do this I will employ a multidisciplinary approach through the application of single-molecule light microscopy techniques. This project will define the relationship between the machinery of transport and the life cycle of axonal proteins.

Lay abstract: The neurons of your body can be incredibly long, for example some have their cell body in your spinal cord and send projections, called axons, down to your muscles to make them move. The cell body of a neuron makes the cellular machinery axons need to function, which is then transported to where it’s needed. Neurons use proteins that make roads and motors to make this happen: the roads are long filaments called microtubules and the motors, kinesin and dynein, walk in opposite directions along them to transport cargo. Some of these transport processes can take many months to reach their final destination, and in neurodegenerative diseases this system of transport can break down entirely. By looking at single molecules of motors behaving within neurons, I aim to understand how this system is regulated, how these processes affect the age of cargo, and develop new approaches to treat neurodegenerative disease.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Lysosome turnover in health, aging and disease
Funder: Wellcome Trust

Abstract: Lysosome dysfunction is implicated in lysosomal storage diseases, and multiple age-related neurodegenerative diseases, including Parkinson’s, Alzheimer’s and age-related macular disease. Lysosomes are signalling organelles central to maintaining cellular homeostasis. Nutrient sensing on the lysosome can lead to nuclear translocation of the transcription factor, TFEB, and lysosomal gene transcription. However, it remains unclear how newly synthesised lysosomal proteins are packaged into new lysosomes and how old/damaged lysosomes are cleared. We recently established models of lysosomal aging/dysfunction in retinal pigment epithelial cells, taking advantage of their huge degradative burden, and identified conditions that upregulate lysosome biogenesis/activity. We propose to identify the trafficking steps and molecular machinery underlying lysosome biogenesis and test the relative contributions of lysosome exocytosis and lysophagy (lysosome autophagy) to cellular clearance of aged/damaged lysosomes. Our ultimate goal is to exploit these mechanisms to promote damaged lysosome clearance or rejuvenation and/or promote lysosome biogenesis for the treatment of diseases where lysosome activity is compromised. Treatment efficacy in upregulating lysosome activity, whilst readily measurable in culture, is difficult to assess in vivo. We will establish a molecular signature of aged/damaged lysosomes in cultured RPE that can be used to identify damaged lysosomes in aged/diseased retinae.

Lay abstract: Damaged cellular components and material taken up from outside the cell can be digested in lysosomes. Accumulation of undigested material occurs in many age-related neurodegenerative diseases like Alzheimer’s disease and age-related macular degeneration (AMD). Recent research aimed at increasing cellular degradative capacity to treat these diseases has led to identification of promoters of synthesis of new lysosome constituents but how these are packaged into new lysosomes and how the old/damaged ones are removed is unclear. Retinal pigment epithelial (RPE) cells engulf and degrade damaged photoreceptor fragments everyday and RPE lysosome dysfunction has been implicated in early AMD. This project aims to determine how new lysosomes are formed and how old/damaged lysosomes are cleared. The development of a molecular signature of old/damaged lysosomes in cultured RPE and its testing for efficacy in identifying dysfunctional lysosomes in aging and diseased retinae will aid development of therapies aimed at improving cellular degradative capacity.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Investigating the molecular basis of cellular diversity in the nervous system
Funder: Wellcome Trust

Abstract: Neural induction is the process responsible for the generation of the entire nervous system. A major question in the field is how this process results in the production of diverse cell types throughout the nervous system, and how it can be applied to regenerative medicine. I recently showed that CDX transcription factors are critical to establish spinal cord fate, but that their capacity to induce spinal cord is lost following neural lineage commitment. Moreover, my preliminary data suggests that CDX factors broadly impact posterior identity in cells, prior to germ layer segregation, that is critical for the generation of different neural subtypes in the nervous system in vivo. In this proposal, the key goals are to: investigate the regulatory mechanisms limiting Cdx2 expression in cells; evaluate how CDX2 represses alternative brainstem fates for the generation of spinal cord; and test the role of CDX in the divergence of neural cells, including neural crest cells, that form distinct fates within the nervous system, in vivo. Taken together, this work will provide molecular insight into how cellular diversity is established in the mammalian nervous system and more generally throughout the body plan.

Lay abstract: In an embryo, the nervous system develops diverse cells types in the brain and spinal cord. How these differences emerge along the anterior-posterior axis remains a major unanswered question. I recently demonstrated that during nervous system development, CDX transcription factors are critical for providing cells with the competence to generate spinal cord. Strikingly, this competence is transient in cells, limiting the production of spinal cord cells to a finite developmental window. The goal of this proposal is to understand how this window is imposed on cells during development, and to explain how CDX activity ensures spinal cord fate by repressing alternative, anterior cell identities. I will investigate how these processes influence cellular diversity throughout the developing nervous system, revealing critical insight into how the mammalian body plan develops. Understanding this process is central to the precise engineering of cells and tissues for use in human disease modelling and regenerative medicine.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Sexy glia: developmental plasticity during glia-derived neurogenesis
Funder: Wellcome Trust

Abstract: The overall goal of this proposal is to elucidate the cellular and molecular mechanisms that regulate natural glia-to-neuron cell-fate switches. Stably differentiated cells can sometimes display a remarkable degree of plasticity and switch fates to another differentiated cell type, in a process termed transdifferentiation. In the vertebrate nervous system, radial glia act as neural progenitors during embryogenesis. Suprisingly, stably differentiated glia can also act as neural progenitors during adult neurogenesis. We have recently discovered two cases in which stably differentiated glial cells undergo a glia-to-neuron cell-fate switch during sexual maturation in the nervous system of C. elegans, allowing us to study these events at the single-cell level in a genetically tractable system. We will combine classic genetic approaches with state-of-the-art molecular and next-generation sequencing approaches to characterise the molecular and epigenetic changes that occur during natural glia-to-neuron transdifferentiation. We will elucidate the role of cell division in this process, identify novel molecular regulators and determine the reprogramming abilities of the factors we identify. Unleashing the neurogenic potential of glia offers tremendous therapeutic possibilities.

Lay abstract: Animals are composed of many different types of cell, each with their own function. In certain circumstances, cells with one function can switch to become cells with a different function. For example, adult newts can regenerate their limbs and this requires cells close by to switch function and produce the different cell types that make up a limb. Harnessing this cell plasticity has enormous therapeutic potential. These cell-type switches can also be observed in our brains. In a few tiny regions of the adult brain, new neurons, the specialised cell type that transmits information, can be generated from glial cells, the other main cell type in the brain, during learning or in response to brain trauma. Understanding, at the molecular level, how these glia-to-neuron switches occur is the goal of this proposal. Conservation of biological processes allows us to study these phenomena in the nematode worm C. elegans, a simple genetic model system. Mechanistic insights into these cell-function switches in the nervous system may, in the future, allow us to regenerate large regions of the brain or to produce neurons in the lab more easily to replace those that are lost in neurodegenerative disease such as Alzheimers and Parkinsons.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Coated vesicle adaptors
Funder: Wellcome Trust

Abstract: Coated vesicles transport molecules from one membrane compartment of the cell (a "donor" compartment) to another ("acceptor") compartment. Adaptors are the components of the coat that select the vesicle cargo. The adaptor protein complexes AP-1 and AP-2 are associated with clathrin-coated vesicles (CCVs), while APs 3, 4, and 5 appear to be clathrin-independent. I have been working on adaptors for over 35 years, but there are still many unanswered questions. We plan to focus on the following areas: 1. The AP-1 pathway. How are the AP-1 donor organelles related to each other, and how are the vesicles recognised so they fuse with the right acceptor compartment? 2. AP-4, AP-5, and hereditary spastic paraplegia. How do AP-4 and AP-5 select cargo and make vesicles, and why do mutations in either of them cause hereditary spastic paraplegia?

Lay abstract: Cells are filled with organelles, or little organs, each with its own particular function. We investigate how proteins called adaptors selectively package molecules into coated vesicles, so they can be transported from one organelle to another. This process is essential for normal cell function, and it is disrupted in certain diseases: some pathogens, such as HIV, are able to hijack adaptors, and there are genetic disorders caused by mutations in adaptors. Using a combination of microscopy (including live cell imaging), biochemistry, and structural biology on different types of cells, we aim to find out more about how the adaptors select cargo, how this is coupled to what happens to the vesicles after they form, and why mutations in two of them, AP-4 and AP-5, cause neurological disorders.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL
Title: Mapping the Genes and Neurons that Regulate Sleep Homeostasis
Funder: Wellcome Trust

Abstract: Although sleep is highly conserved and has a major impact on human health, the genetic and neuronal mechanisms that regulate the timing and amount of sleep remain poorly resolved. From a combination of whole-brain activity mapping, targeted gene editing, and behavioural analysis, we have discovered that neurons in the zebrafish preoptic area that express the neuropeptide Galanin become activated during rebound sleep and that proper sleep homeostasis requires functional Galanin. We will now use RNA sequencing, pharmacology, and mutant analysis to dissect the signals that converge onto Galanin-mediated sleep homeostasis. Second, we will leverage the optical translucency of the zebrafish brain and genetically encoded calcium indicators to image Galanin neurons’ activity in relation to known wake-promoting circuits, such as Hypocretin and Noradrenaline neurons, in vivo. Finally, we will use chemogenetic tools to manipulate the activity of Galanin neurons during and after normal and homeostatic rebound sleep to elucidate the functional role these neurons play in sleep regulation.

Lay abstract: Although we spend a third of our lives asleep, how and why the brain switches off at night remains one of the great mysteries of science. Especially unclear are the mechanisms that trigger increases in sleep pressure, which is the increased drive to sleep after periods of prolonged wakefulness. Since sleep is nearly universal in the animal kingdom, we can use simpler organisms like the zebrafish to identify the signals that drive sleep pressure and map where these signals are read out in the brain. First, we will generate genetically altered zebrafish that have deficits in their response to sleep deprivation. Second, we will take advantage of the optical translucency of the larval zebrafish brain to watch brain activity during changes in sleep pressure. As many people suffer adverse health consequences from poor sleep, any advance in our basic understanding of how sleep works could ultimately have a clinical impact.

Research activity codes: 1.1 NORMAL BIOLOGICAL DEVELOPMENT AND FUNCTIONING
Health categories: GENERIC HEALTH RELEVANCE;NEUROLOGICAL