Understanding the impact of drugs on the early placenta
Supervisor: Dr Catherine Aiken, Associate Professor and Honorary Consultant (firstname.lastname@example.org)
Principle Supervisor Department: Obstetrics and Gynaecology
Despite the high global burden of maternal and neonatal morbidity and mortality caused by pregnancy complications, there are very few drugs available to tackle pregnancy-specific diseases. Many complications of pregnancy, for example pre-eclampsia, are initiated during early pregnancy. However there are currently no therapeutic options that currently target early placental development.
We aim to develop new methodology to test the effects of drugs on placental trophoblast cells in early pregnancy.
We will use a combination of model systems, including trophoblast organoids, which are a novel methodological advance in early pregnancy research, and human trophoblast stem cells. Crucially these models both have the capacity to differentiate under specific culture conditions to extravillous trophoblast, thus modelling the early stages of connection between maternal and placental tissues. The platform will be used to test drugs used for pregnancy-specific conditions as well as those taken during pregnancy for other reasons (including pre-existing conditions).
We will evaluate the impact of agents, including metformin and aspirin, on (i) first trimester placental growth and extravillous trophoblast differentiation (via time-lapse imaging) and (ii) first trimester placental cellular respiration and ATP production (via Seahorse respirometry). These techniques have been piloted with our trophoblast models, and several have already been established within my research group. These core assays will be supplemented by additional testing where relevant to test specific agents, for example labelled substrate tracking or Oxygraph respirometry. The project aims to identify drugs with the potential to reduce placental complications that arise from early pregnancy.
Metabolic determinants of early placental development
Supervisor: Dr Irving Aye, Group Leader (email@example.com)
Principle Supervisor Department: Obstetrics & Gynaecology
During early development, placental cells called trophoblasts face diverse challenges including nutrient and oxygen-limited microenvironments and changing environmental conditions. It is also during this stage that vast changes in gene expression coincide with reprogramming of cellular metabolism. How trophoblasts assess and respond to their metabolic resources to achieve a coordinated effect on cell proliferation, differentiation, and placental development is unclear. Cell metabolism is conventionally viewed as a means of obtaining bioenergy or building blocks for growth. However, metabolic intermediates function as rate-limiting substrates or co-factors in a variety of epigenetic processes.
This project aims to understand the links between metabolism and epigenetic programs directing trophoblast stemness and differentiation. Key questions to be addressed are: How does the placenta respond and adapt to changes in varying environmental conditions? How does cellular metabolism influence epigenetic networks in placental development? What is the impact of metabolic dysfunction on placental development and pregnancy outcome?
The candidate will utilise the recently derived human trophoblast stem cells and organoids. Additionally, training will be provided in the following state-of-the-art research techniques:
• 2D and 3D culture of human trophoblast stem cells
• Metabolic phenotyping and profiling using extracellular flux analysis (using the Seahorse Bioanalyzer) and metabolomics
• Gene targeting using Crispr/Cas9, si/shRNA transfection, and lentiviral transduction
• Wet-lab based approaches for RNA-seq, single-cell RNA-seq, ChIP-seq, and bisulfite-seq etc
Addressing these fundamental biological questions may help us understand novel mechanisms of placental-related pregnancy complications such as miscarriage, preeclampsia and fetal growth restriction.
Informal enquiries can be made to Dr Irving Aye: firstname.lastname@example.org
Insulin and fat metabolism in preterm infants and relationship to early growth
Supervisor: Dr Kathryn Beardsall, Associate Professor/Honorary Neonatal Consultant (email@example.com)
Principle Supervisor Department: Paediatrics
Prematurity and being born small for gestational age are associated with heart disease, abnormal fat levels and type 2 diabetes in later life. Preterm infants often experience growth restriction both before birth and immediately after birth. However, there is a lack of information on the impact on early metabolism such as glucose levels (an indicator of insulin sensitivity) and lipid levels in the blood and later risk. Preterm babies have poor glucose control and we have shown marked differences in fat levels in their blood compared to babies born at term.
This project will combine unique data collected using continuous glucose monitoring (CGM) and blood spots for the detailed measurement of fat metabolism in preterm infants in the perinatal period and into early childhood. It will combine these methods to determine the relationship of glucose control and insulin sensitivity to fat metabolism in preterm infants and whether abnormal fat metabolism persists in childhood.
Myosin motor function in microglia and astrocytes
Supervisor: Professor Folma Buss, Professor in Molecular and Cellular Biology (firstname.lastname@example.org)
Principle Supervisor Department: Cambridge Institute for Medical Research
Intracellular transport is driven by nanoscale motor proteins that use energy derived from ATP hydrolysis to move cargo between different cellular compartments along cytoskeletal tracks. Myosin motor proteins perform a wide range of fundamental functions in eukaryotic cells by providing force generation, transport or tethering capacity. Our aim is to delineate the distinct functions performed by myosin motors within human cells, while also determining the mechanisms that regulate motor activity and motor-cargo attachment. Understanding these fundamental cellular processes is crucial as the dysfunction of myosin motors are linked to a wide range of disorders including deafness, cardiomyopathy, neurodegeneration and cancer. Myosin motors are established drug targets and therefore a detailed understanding of the cellular functions of myosin motors and the molecular mechanisms that regulate their cellular activities are essential to design new therapeutic approaches.
The focus of this PhD project is to analyse the specialised cellular functions of myosin motors in glial cells in the central nervous system. We will utilize a multidisciplinary approach to determine the role of myosin motors and their cargo adaptor proteins in astrocytes and microglia to understand how changes in their expression pattern are linked to neuroinflammation.
In this project the student will use a wide variety of cell biological, biochemical and molecular biology techniques including super resolution live cell imaging, culture of primary and iPSC-derived glial cells, advanced proteomics and in situ proximity labelling alongside other protein-protein interaction studies.
Characterising novel regulators of insulin-regulated glucose uptake
Supervisor: Dr Daniel Fazakerley, Principal Investigator (email@example.com)
Principle Supervisor Department: Clinical Biochemistry
Insulin lowers blood glucose by increasing glucose transport into fat and muscle tissues. Impaired insulin responses in these tissues (i.e., insulin resistance) is a risk factor for metabolic diseases such as type 2 diabetes. In fat and muscle cells, insulin signalling promotes the translocation of the glucose transporter GLUT4 to the cell surface to facilitate glucose uptake. We do not have a complete understanding of how insulin stimulates GLUT4 translocation, nor do we understand how this process goes wrong in insulin resistance.
Through a series of ‘omics analysis, including human genetics and subcellular proteomics, we have identified novel regulators of insulin-stimulated GLUT4 trafficking. The aim of this project is to find out how these work. This knowledge will improve our understanding of insulin-regulated glucose transport and possibly reveal new way to target this pathway to overcome insulin resistance.
Investigating the molecular consequence of Dishevelled mutations in skeletal dysplasias
Supervisor: Dr Melissa Gammons, Wellcome Career Development Fellow, (firstname.lastname@example.org)
Principle Supervisor Department: Department of Medical Genetics
Genetic defects in components of Wnt signaling pathways cause multiple developmental disorders, including the rare skeletal dysplasia known as Robinow Syndrome (RS), characterized by skeletal, genital, and craniofacial abnormalities. In addition, misregulation of Wnt signaling, resulting from mutations or abnormal expression, drives the metastatic progression of many cancers.
A critical transducer of Wnts is Disheveled (DVL1-3 in mammals), a cytoplasmic adapter protein that directly binds to the intracellular face of the Wnt receptor Frizzled family. It also self-associates to assemble phase-separated multiprotein complexes, known as signalosomes, which act as signaling hubs. Frameshift mutations that alter the C-terminus of Disheveled have been identified in individuals with autosomal dominant RS. Interestingly, identical mutations have also been observed in dog breeds, such as bulldogs, exhibiting Robinow-like morphological features. However, it remains unclear how Disheveled RS-associated mutants disrupt Wnt signaling at the molecular level.
This project will employ state-of-the-art proteomics screens to systematically identify novel binding partners whose association with RS-mutant Disheveled differs from that with wild-type controls. Candidate hits will be deleted using CRISPR editing and tested in innovative cell-based functional assays to determine their importance in Wnt signaling and signalosome assembly. This will be complemented by biochemical and biophysical assays to define their direct interactions and design disabling point mutations to be incorporated into our cell-based assay system.
This fundamental research project has the potential to break new scientific ground by identifying novel regulators of Wnt signaling pathways and providing valuable insights into the molecular mechanisms of disease-associated Disheveled mutants. Given the significance of Wnt signaling in development and disease, this work will aid in the development of more targeted therapies with a direct impact on human health. The student will receive support, guidance, and expert training in cutting-edge molecular biology techniques and transferable skills necessary for the next stage of their career.
Elucidating the Role of Lipids in Golgi Function, Sorting, and Disease Implications
Supervisor: Dr David Gershlick, Henry Dale Fellow (email@example.com)
Principle Supervisor Department: Cambridge Institute for Medical Research
The Golgi apparatus, a central organelle in the cell, plays a pivotal role in processing and packaging proteins and lipids for intracellular transport. The intricacies of Golgi sorting are influenced not just by proteins but also by lipids, which form the bulk of its structure. While the relationship between lipid constitution and Golgi function is evident, the precise role lipids play in Golgi sorting remains elusive. Lipids, particularly those in specialised domains, might have a larger role in determining the sorting routes within the Golgi.
For this PhD project, the focus will be on elucidating the molecular mechanisms by which lipids impact Golgi function and sorting. The key objectives include:
• Assessing the role of lipids in determining Golgi sorting pathways.
• Investigating the effects of lipid enzyme or transfer inhibitors using the RUSH system.
• Studying the lipid dynamics during Golgi exit using novel methodologies.
• Using the insights developed on the relationship between membrane proteins and lipids to develop novel therapeutics.
To achieve these objectives, the research will employ an array of advanced methodologies. Techniques such as flipper probes, which bind specifically to particular lipid species, and solvatochromic dyes that alter fluorescence based on their environmental polarity will be used to study lipid behaviour and distribution. This will be complemented by state-of-the-art imaging, including super-resolution live cell imaging, to visualise lipid dynamics within the Golgi.
Disruptions in Golgi functions are associated with a variety of diseases. An in-depth understanding of the role of lipids in Golgi functions could provide insights into these diseases at a molecular level. Furthermore, considering the therapeutic potential of targeting Golgi functions, this research can pave the way for new treatment strategies, making it both fundamental and translational in nature.
Gut hormones in diabetes and obesity
Supervisor: Professor Fiona Gribble, Professor of Endocrine Physiology (firstname.lastname@example.org)
Principle Supervisor Department: Clinical Biochemistry
Gut hormones control post-prandial metabolism and appetite, and have been harnessed for some very successful new treatments for type 2 diabetes and obesity, based on the hormone GLP-1 (glucagon-like peptide-1). Our group is interested in how gut hormones like GLP-1 are released from the gut, and how they act on target tissues.
To enable research into the rare enteroendocrine cells that produce gut hormones, we genetically engineer human intestinal organoids to express fluorescent sensors under the control of cell-specific hormonal promoters. These organoid lines allow us to identify and perform dynamic cell imaging and electrophysiology of identified enteroendocrine cell types in the human gut, which when combined with results of RNA sequencing are used to investigate molecular signalling pathways underlying responses to different nutritional and pharmacological stimuli at the single cell level.
This project will investigate the roles of signalling pathways involving cyclic AMP and ERK in GLP-1 producing L-cells, and their importance for stimulus detection and exocytosis in L-cells. We will perform live cell imaging of cAMP, calcium and pERK in human L-cells in response to different stimuli, after generating new organoid lines by CRISPR-Cas9 expressing genetically encoded fluorescent sensors for these different signalling pathways. The importance of candidate regulatory proteins will be examined by generating gene knockouts by CRISPR-Cas9, and effects on hormone secretion will be measured by immunoassay and peptide mass spectrometry.
Overall, we aim to develop new treatments for metabolic disease based on targeting the gut endocrine system, which requires a deeper understanding of different signalling pathways in enteroendocrine cells.
Alpha-synuclein phase separation and the role of S129 phosphorylation
Supervisor: Dr Janin Lautenschläger (email@example.com)
Principle Supervisor Department: CIMR
Alpha-synuclein is small synaptic protein shown to be involved in Parkinson’s disease, however its function is only incompletely understood. Our lab is centred around the concept of protein phase separation at the synapse, and we have recently demonstrated that alpha-synuclein phase separation is regulated by a protein interaction partner, namely VAMP2. Phosphorylation of alpha-synuclein at residue 129 is a well described disease marker, however it has been recently described that S129 phosphorylation is dynamically regulated during synaptic function, regulating its protein-protein interactions (Ramalingam et al. 2023 npj Parkinsons disease, Parra-Rivas et al. 2022 BioRxiv). One of these partners found is VAMP2. With this project we aim to study how S129 phosphorylation influences VAMP-mediated alpha-synuclein phase separation. Combining in vitro experiments on model membranes and in cell studies this project will deliver new insights on the physiological function of alpha-synuclein.
The Role of Placental Exosomes as Mediators of Programming during Obese Diabetic Pregnancies
Supervisor: Professor Susan Ozanne, Professor of Developmental Endocrinology (firstname.lastname@example.org)
Principle Supervisor Department: Institute of Metabolic Science
The placenta is the interface between mother and fetus, integrating signals between the two. One means of communication is through the release of placental extra-cellular vesicles (EVs). These are small membrane bound organelles that contain proteins, metabolites and RNA including miRNAs. Placental EV content is regulated in response to the maternal environment and therefore could mediate the known detrimental effects of an in utero obesogenic/diabetic environment on the offspring.
This project will explore the underlying mechanisms by which changes in placental EV content can influence the short- and long- term effects on fetal and offspring metabolism. The project will involve: (1) profiling of the protein and miRNA content of placental EVs isolated from lean and obese murine pregnancies, (2) a combination of in vitro and in vivo experiments to establish the functional consequences of the changes in placental EV protein and miRNA content, (3) labelling of placental EVs to identify the target tissues with which they fuse and (4) establishing how placental EV content by treatment of glucose intolerance during an obese pregnancy.
Characterisation of the fat distribution within skeletal muscle
Supervisor: Dr Alison Sleigh, Principal Research Associate (email@example.com)
Principle Supervisor Department: Clinical Neurosciences
Fatty infiltration of skeletal muscle is associated with aging, fatigue and muscle atrophy. It has been shown that this infiltration is not uniform, varying both within and between muscle groups. The distribution of this infiltration may provide information on the mechanisms involved.
This project will use MRI to investigate the fat infiltration in a group of patients with mitochondrial myopathy as well as healthy controls and will compare these with other measures of physical and mitochondrial function.
This project can be tailored to your skills and interests, with either a more physiological approach, or a project more focused on image analysis and techniques to automate muscle segmentation such as deep learning. This project may also include magnetic resonance spectroscopy measures to provide non-invasive biochemical information.