To sense their local environment and respond to stimuli, our cells grow antenna-like projections called cilia. These antennae are vital in many important sensory functions, allowing us to see, smell and to develop properly as embryos. Improper function of cilia is linked with varied diseases from sight impairment to obesity. Currently we lack a good understanding of how cilia work, and so finding ways to treat these diseases is extremely difficult. A crucial step in understanding these antennae is discovering how special components called motor proteins work within them. Motor proteins use energy to transport different components that the cell needs. A motor protein called dynein-2 can walk along microtubule tracks inside cilia carrying cargo needed for sensing and signalling. Our understanding of how dynein-2 works is currently limited and this is what I want to elucidate. I will use different types of powerful electron and light microscope and sophisticated artificial-intelligence-enabled image processing methods to study i) what dynein-2 looks like when it is working properly and when it is causing disease, ii) how dynein-2 steps along the microtubule tracks inside cilia and iii) how dynein-2 is switched on to carry its cargo. These are questions fundamental to understanding how dynein-2 and cilia function, underpinning their many physiological roles. The answers generated in this research will aid efforts to fix dynein-2 when it goes wrong in disease, and generate workflows to understand this and other medically important molecular machinery in unprecedented depth.

Chronic hepatitis B (CHB), caused by hepatitis B virus (HBV), is a leading cause of liver cirrhosis, liver failure and hepatocellular carcinoma (HCC). Of the 350 million chronic HBV carriers worldwide ~20% will die from terminal liver disease. 14 million Europeans live with CHB; the associated mortality rate is ~36,000 deaths/year. Current treatments offer at best control of infection but no cure. Chronicity relies on a unique intracellular viral replication intermediate termed covalently closed circular (ccc) DNA which ensures progeny virus production; its eradication is the prerequisite for a cure. However, how cccDNA is generated from the relaxed circular (RC) DNA genome present in infectious virions is not known, except that the multiple conversion steps required must largely depend on host factors. To identify such host factors as novel antiviral targets, this proposal combines the complementary competences of four HBV-experienced partner labs (Baumert & Brino, France; Bielawski, Poland; Nassal, Germany) using state-of-the-art technologies and most recent virological advances/findings. These include RNAi-based screening and preclinical validation of targets by advanced cell-culture systems, including HBV-infectable cell lines and novel HBV reporter vectors. HBV-relevant host factors will be explored as antiviral targets. For most rapid translation into the clinic, a lab renowned for development of antivirals (Neyts & Dallmeier, Leuven, Belgium) will join as non-funded associate partner to initiate HTS screening for small-compound host factor inhibitors. Target discovery will be complemented by identification of pertinent viral and host factor polymorphisms in clinical HBV patient sample repositories (Baumert & Bielewski), using advanced mass spectrometry (MS). Patient-specific polymorphisms plus clinical data will be merged into a correlative virus/host factor/disease data base to reveal novel biomarkers for progression of liver disease and personalized treatment approaches. To help exploit project-specific R&D results, the partner SME VIRONEXX (Strasbourg, F) will professionally assess market potential via established contacts with major pharma; this feedback will help early-on to focus the program on targets with the highest foreseeable impact for biomarker and drug development. We expect this project to substantially advance basic knowledge of a key issue in HBV pathogenicity and allow identification of new targets that are crucial for the eventual cure of chronic hepatitis B. Moreover, the project contributes to developing and jointly using EU-wide data bases and technology platforms.