We aim to elucidate the molecular mechanisms that control the assembly, maintenance and function of the kinetochore and broader mitotic spindle. We will build on the proteomic and microscopy techniques we have developed to unpick their regulation in detail; to understand how this controls chromosome segregation; how it varies such that cells can switch between symmetric and asymmetric cell division; how it is involved in controlling cell fate decisions; and how these processes might go awry in development and cancer.
The lab has distinguished itself through its methodologies and rigorous, quantitative approach. We are exploiting our Synthetic Physical Interaction (SPI) and high-throughput imaging methods, as well as growing our collaborations and pursuing new state-of-the-art methodologies. We aim to integrate our findings, using computational and experimental methods to construct a systems level understanding of the kinetochore and its complex and dynamic role in the cell.
Our previous work has suggested that phosphorylation plays a central role in kinetochore control – something that we are exploring in detail by identifying and characterising key regulatory kinases and phosphatases. We will map where and when in the kinetochore these proteins act, and how they connect with other cell processes. We aim to extend the SPI system to construct synthetic regulatory pathways.
Chromatin modification is now thought to be an important means of kinetochore regulation in mammalian and yeast cells, and we plan to investigate this emerging idea. We are developing a yeast system based on CRISPR-Cas9 that allows us to send chromatin modifying proteins, such as a histone deacetylase, to each of several thousand specific sites across the yeast genome. We have already shown that targeted deacetylation at the centromere affects cell growth, and we plan to systematically test the role of other chromatin modifying proteins to see if targeted epigenetic changes alter chromatin structure or function. We are also extending this work, using our CRISPR-based engineering system to test the importance of chromatin modifications throughout the genome.
We will continue to pinpoint the mechanisms linking kinetochore regulation and asymmetric cell division. Our previous work has identified a group of candidate genes involved in both processes and we aim to refine this to identify master regulators that are important in cell fate determination. We are testing the hypothesis that these master regulators play a role in the aberrant asymmetric cell division and chromosome segregation seen in many human cancers.
We hypothesise that microtubules and the MTOC have a more dynamic role in kinetochore regulation than has been appreciated, and to test this we have developed a way to automatically mine the databank of images we have collected from around 6000 yeast mutants to identify kinetochore regulators that also affect microtubules or the MTOC. As part of our interdisciplinary approach, we are strengthening the numerical and computational capabilities of the lab. Working with computational biologist Attila Czikas-Nagy at King’s College London, we have recruited a joint PhD student with expertise in mathematics. The aim is to synthesise our growing data on kinetochore and MTOC regulation into a mathematical model of the mitotic spindle that can be used to simulate kinetochore function and generate experimentally testable hypotheses.
We are also fortunate to have a collaboration with a biophotonics group at Imperial College London that will allow us to use high-throughput, super resolution imaging to precisely map the location of kinetochore regulators. We are using this to explore some intriguing links between kinetochore function and DNA repair, focused on the role of the DNA repair protein Rdh54.
We are committed to making all of our tools and data available online, partly through the BBSRC next generation imaging database. We have incorporated our SPI data on forced interactions into a web-tool and are working on adding our microscopy data too. This could serve as an open-access online resource for exploring spatial and temporal regulation within the cell.