Functions Of A Novel Conserved DNA Damage Response Protein Family In Telomere Stability
Funder
National Health and Medical Research Council
Funding Amount
$282,825.00
Summary
The free DNA ends of chromosomes, termed telomeres, generally resemble broken DNA. Because broken DNA is a major contributing factor to the onset of cancer, cells try to fix broken ends. However, in case of telomeres, such repair processes have to be prevented because otherwise different chromosomes would fuse with each other. Fused chromosomes are very fragile and cannot be evenly distributed between dividing cells, and are therefore another important trigger of cancer development. Therefore, c ....The free DNA ends of chromosomes, termed telomeres, generally resemble broken DNA. Because broken DNA is a major contributing factor to the onset of cancer, cells try to fix broken ends. However, in case of telomeres, such repair processes have to be prevented because otherwise different chromosomes would fuse with each other. Fused chromosomes are very fragile and cannot be evenly distributed between dividing cells, and are therefore another important trigger of cancer development. Therefore, chromosome ends are covered by a cap, which hides them from the DNA damage response machinery. From these considerations it is clear that there are close connections between the cellular DNA damage response and chromosome ends. Moreover, recently it has become clear that DNA damage proteins are also required to stop normal cells from growing, a process termed senescence. Senescence is a consequence of shortened chromosome ends, and does not occur in cancer cells. Altogether, it is clear that DNA breaks and senescence are two of the major questions for our understanding of cancer development. We have identified a novel conserved protein family that is involved in the response to DNA damage in yeast and humans. In addition, the yeast Mdt1 protein is a very sensitive indicator of changes in the telomere cap. Absence of proteins that organise the cap leads to the addition of several phosphate groups to the Mdt1 protein. We propose that phosphate-coupled Mdt1 prevents chromosome ends from fusion with each other, or from fusing with broken DNA ends after widespread damage. As a consequence, cells that have mild cap defects die at an >1000-fold increased rate in response to DNA damage when they also lack Mdt1. As part of this application we want to find out the precise mechanism by which Mdt1 stabilises chromosome ends, and test our hypothesis that the corresponding human protein termed ASCIZ also has similar functions in protecting chromosome ends.Read moreRead less
Understanding how cells compact and segregate DNA in vertebrates. How a cell compacts and divides its DNA is still a major unanswered question in biology. This project will determine the way in which a cell compacts its DNA nearly ten thousand fold to allow the faithful and accurate segregation to daughter nuclei.
Understanding Mitotic Telomere Deprotection. This project aims to study telomeres, the DNA and protein structures that protect chromosome ends. During cell division, cells under stress intentionally uncap their telomeres. This project expects to generate new knowledge that challenges the conventional notion of telomeres as static elements, showing instead that telomeres can be dynamic signalling hubs. Expected outcomes of this project include an understanding of the genetic, proteomic, and signa ....Understanding Mitotic Telomere Deprotection. This project aims to study telomeres, the DNA and protein structures that protect chromosome ends. During cell division, cells under stress intentionally uncap their telomeres. This project expects to generate new knowledge that challenges the conventional notion of telomeres as static elements, showing instead that telomeres can be dynamic signalling hubs. Expected outcomes of this project include an understanding of the genetic, proteomic, and signalling pathways involved in this novel phenomenon. This should provide significant benefits to our fundamental understanding of biological processes that protect human genomes and provide a valuable dataset for research on telomere biology, DNA repair, and genome stability.Read moreRead less
Identification of Biological pathways regulated by circular RNAs. Circular RNAs (circRNAs) are a, recently discovered molecule. circRNAs are highly abundant and expressed in a tissue and disease specific manner. Yet, currently the understanding of how circRNAs regulate biological processes is very poor. This project aims to use pooled shRNA libraries to screen a large panel of cell lines and systematically identify cellular activities that are regulated by circRNAs. The expected outcome of this ....Identification of Biological pathways regulated by circular RNAs. Circular RNAs (circRNAs) are a, recently discovered molecule. circRNAs are highly abundant and expressed in a tissue and disease specific manner. Yet, currently the understanding of how circRNAs regulate biological processes is very poor. This project aims to use pooled shRNA libraries to screen a large panel of cell lines and systematically identify cellular activities that are regulated by circRNAs. The expected outcome of this study will be a catalogue of functionally active circRNAs. Over the past decades, the wealth of knowledge on the function of linear mRNAs has had a significant impact on medicine and agriculture. Similarly understanding how circRNAs regulate cellular activities may have an analogous impact on humans.Read moreRead less
Structural domains of beta-tubulin and their role in microtubule dynamics and transport. This study aims to obtain a fundamental understanding of how the structural domains of the cytoskeletal protein beta-tubulin are involved in microtubule structures during cell division and vesicular transport. Using gene-editing technology and coupling this with cell biological approaches and high-resolution cell imaging will enable detailed analysis of the role of beta-tubulin domains in these important cel ....Structural domains of beta-tubulin and their role in microtubule dynamics and transport. This study aims to obtain a fundamental understanding of how the structural domains of the cytoskeletal protein beta-tubulin are involved in microtubule structures during cell division and vesicular transport. Using gene-editing technology and coupling this with cell biological approaches and high-resolution cell imaging will enable detailed analysis of the role of beta-tubulin domains in these important cellular processes. The outcomes will include fundamental new knowledge in cell biology and lead to the development of unique biological models that can be used to understand disease.Read moreRead less
Differentiation of effector and tissue regulatory T cells . Regulatory T cells (Tregs) populate almost every organ of the body and play a central role in preventing inflammation and maintaining health. To exercise these functions, Tregs undergo a developmental program, the details of which are poorly known. This project will utilize newly developed biological tools and state-of-the-art technology to uncover the molecular mechanisms that govern Treg development and function. The project will gene ....Differentiation of effector and tissue regulatory T cells . Regulatory T cells (Tregs) populate almost every organ of the body and play a central role in preventing inflammation and maintaining health. To exercise these functions, Tregs undergo a developmental program, the details of which are poorly known. This project will utilize newly developed biological tools and state-of-the-art technology to uncover the molecular mechanisms that govern Treg development and function. The project will generate basic scientific knowledge and new intellectual property that will afford new opportunities for research and development. The outcomes of this project will help to devise strategies to treat diseases such as autoimmunity, cancer and metabolic syndrome, and will thus benefit veterinary and human health.Read moreRead less
Discovery Early Career Researcher Award - Grant ID: DE160100620
Funder
Australian Research Council
Funding Amount
$378,000.00
Summary
Mechanisms of controlled gene expression in cells and organisms. The goal of this project is to reveal the nature of a cellular mechanism that has a major influence on gene expression in all eukaryotic cells. How gene expression is controlled is of fundamental importance to all life forms. The project plans to develop molecular tools that enable the visualisation and interrogation of this gene regulatory mechanism in live cells, tissues and whole organisms. The outcomes are anticipated to lead t ....Mechanisms of controlled gene expression in cells and organisms. The goal of this project is to reveal the nature of a cellular mechanism that has a major influence on gene expression in all eukaryotic cells. How gene expression is controlled is of fundamental importance to all life forms. The project plans to develop molecular tools that enable the visualisation and interrogation of this gene regulatory mechanism in live cells, tissues and whole organisms. The outcomes are anticipated to lead to an essential understanding of how cells respond to physiological and environmental cues by coordinating changes in gene expression, and to provide potential avenues towards manipulation for pharmaceutical, agricultural and biotechnology purposes.Read moreRead less
Regulating the composition of biomolecular condensates in living cells. Biomolecular condensation is a novel organising principle of living cells, driven by ‘unmixing’ of the cellular contents into compartments. It is observed from plants to animals and is involved in diverse processes from how cells repair DNA to how they perceive signals. This project aims to reveal how human cells control the composition of condensates, which is critical for their function. It expects to uncover new regulator ....Regulating the composition of biomolecular condensates in living cells. Biomolecular condensation is a novel organising principle of living cells, driven by ‘unmixing’ of the cellular contents into compartments. It is observed from plants to animals and is involved in diverse processes from how cells repair DNA to how they perceive signals. This project aims to reveal how human cells control the composition of condensates, which is critical for their function. It expects to uncover new regulatory principles of cellular organisation by combining methods from quantitative cell biology and statistical physics. Expected benefits include building Australia’s capability in the potentially transformational field of biomolecular condensates, which has diverse future biotechnology applications in health and agriculture.Read moreRead less
Understanding how dynamic changes in chromatin composition control genome function. DNA is tightly packaged in eukaryotic cells as chromatin. Important genetic processes, such as transcription, require manipulation of chromatin structure to access the DNA. The cell sets up specialised chromatin structures to regulate these processes. Currently, precise molecular details of these specialised structures are limited. This project will push the envelope of an in vitro model chromatin system and dete ....Understanding how dynamic changes in chromatin composition control genome function. DNA is tightly packaged in eukaryotic cells as chromatin. Important genetic processes, such as transcription, require manipulation of chromatin structure to access the DNA. The cell sets up specialised chromatin structures to regulate these processes. Currently, precise molecular details of these specialised structures are limited. This project will push the envelope of an in vitro model chromatin system and determine the architecture of several chromatin states with unique functional implications inside the cell. This will unravel the molecular instructions that define how our genomes are organised, significantly advancing our knowledge of fundamental eukaryotic genome biology and paving the way for the future development of new tools and therapies.Read moreRead less
Road rules for traffic on DNA - gene regulation by encounters between transcribing RNA polymerases and DNA-bound proteins. This project addresses a widespread but poorly understood phenomenon in gene regulation. The work will support Australian industries by supplying new tools for manipulation of gene expression for industrial and medical applications and will provide unique opportunities for Australian students in this emerging field.