Periodic Reporting for period 2 - NeuroCentro (Novel mechanisms of neurogenesis- from centrosome to engineering migration)
Okres sprawozdawczy: 2022-04-01 do 2023-09-30
This project deals with the role of a structure in cells, the centrosome, that has been known to regulate the cytoskeleton of cells and via this affects processes such as cell division and migration. Our work shows that the centrosome is composed by many different proteins in different cells with unexpected functions - for example we found many RNA-binding proteins and even proteins that process RNA (e.g. "splicing") which normally takes place in the nucleus. Importantly, these proteins are relevant in development and disease, as mutations of the proteins we found at the centrosome are linked to certain diseases. For example, some of these RNA binding proteins are present in all cells of our body, but when mutated in patients the disease only affects the brain. This is an important general question, why ubiquitous proteins when mutated or lost only affect specific tissues or organs. Beyond this very specific focus, we also develop and use techniques in this proposal that are helpful to generally understand how the brain assembles correctly, how its cell type diversity is achieved and how they reach their proper position to allow the complex functions of the brain.
The overall objectives of this grant are to understand the cell-type-specific functions that some of the proteins that are at the centrosome in a cell-type-specific function exert. A focus of this are the RNA-binding proteins, but also cytoskeletal proteins that may regulate unexpected functions. A second main aim is to understand the role of the centrosome in different modes of migration and if its distinct composition contributes to distinct migration modes. Finally, we are aiming to help cells that failed to migrate in a disease context by correcting their migration, e.g. by manipulating specific (centrosome) proteins.
The overall objectives of this grant are to understand the cell-type-specific functions that some of the proteins that are at the centrosome in a cell-type-specific function exert. A focus of this are the RNA-binding proteins, but also cytoskeletal proteins that may regulate unexpected functions. A second main aim is to understand the role of the centrosome in different modes of migration and if its distinct composition contributes to distinct migration modes. Finally, we are aiming to help cells that failed to migrate in a disease context by correcting their migration, e.g. by manipulating specific (centrosome) proteins.
The main result achieved so far is the discovery that centrosomes of brain cells have many proteins associated that there previously not foound at the centrosome in other cells. Moreover, the centrosome of neural stem cells differs by half of all proteins from the centrosome of neurons. Particularly surprising was to find so many RNA-binding proteins, amongst them even ubiquitous proteins, present in almost all cell types. We could demonstrate that localization at the centrosome matters for disease as only where the ubiquotous protein PRPF6 was at the centrosome is there a disease phenotype. We could further demonstrate that this factor brings some of its splicing targets to the centrosome for local translation there and this influences the disease phenotype (O'neill et al., Science 2022).
Interestingly, specific proteins associated with the centrosome also allow separating its function in cell migration versus axon formation, as recently published in a collaborative work with Frank Bradke (Vinpoal et al., Neuron 2023).
In addition, we have used some of the tools to manipulate gene expression in direct reprogramming. We are also interested to compare development of cells normally in the developing brain, versus transplantation into an adult brain, as the latter is important for brain repair.
Interestingly, specific proteins associated with the centrosome also allow separating its function in cell migration versus axon formation, as recently published in a collaborative work with Frank Bradke (Vinpoal et al., Neuron 2023).
In addition, we have used some of the tools to manipulate gene expression in direct reprogramming. We are also interested to compare development of cells normally in the developing brain, versus transplantation into an adult brain, as the latter is important for brain repair.
The discovery that the centrosome is so different between cell types, even the closely related neural stem cells and neurons is a major breakthrough. Likewise it was very unexpected to find splicing factors at the centrosome which led to another breakthrough discovery, namely that tissue- and cell type-specific localization can convey organ-specific phenotypes in disease. These breakthrough discoveries were published in O'Neill et al., Science 2022.