Epigenetic Silencing Of Retroelements In Mammalian Stem Cells: A Role For RNA Interference?
Funder
National Health and Medical Research Council
Funding Amount
$296,980.00
Summary
Now that the human genome has been sequenced, all the genes which encode the bricks and mortar of our cells have been defined. A major question remains: how are all these genes controlled and co-ordinated? What turns them on or off at precisely the right time? In this project we wish to test whether a newly-discovered mechanism of turning genes off in plants and flies also works in mammals. If we demonstrate this mechanism then it may help us to improve gene therapy - a novel form of medical tre ....Now that the human genome has been sequenced, all the genes which encode the bricks and mortar of our cells have been defined. A major question remains: how are all these genes controlled and co-ordinated? What turns them on or off at precisely the right time? In this project we wish to test whether a newly-discovered mechanism of turning genes off in plants and flies also works in mammals. If we demonstrate this mechanism then it may help us to improve gene therapy - a novel form of medical treatment in which healthy genes are used to replace defective genes in cells. Both inherited diseases, like hemophilia, and acquired diseases, like cancer, have been considered appropriate targets for gene therapies. Surprisingly, however, the promises of gene therapy have not kept up with expectations. In attempting to achieve clinically relevant results, viruses (masters of forcing infected cells to do their bidding) have been harnessed to deliver healthy genes into diseased cells. A major problem has been that the modified, safe viruses used clinically have not been efficient at achieving sustained production of healthy gene products. In examining the question of what turns gene off, we will attack the problem of sustainability of gene therapy by defining the mechanisms involved in switching gene therapy viruses off. If we can understand what switches viral genes off in cells, then we should be able to devise means to avoid the 'off switch' and thereby provide durable treatments for many types of cancer. In the studies described , we will attack this problem using a number of different, but complementary approaches.Read moreRead less
All cells in the blood are the descendants of a single cell type, the stem cell. Stem cells are found in the bone marrow and throughout life have the unique ability to generate more of themselves (termed self-renewal) as well as to produce the functional cell types of the blood, ie. red and white blood cells. This project concentrates on the processes by which these stem cells can achieve these two functions. What are the genes that enable a stem cell to have this self-renewal characteristic and ....All cells in the blood are the descendants of a single cell type, the stem cell. Stem cells are found in the bone marrow and throughout life have the unique ability to generate more of themselves (termed self-renewal) as well as to produce the functional cell types of the blood, ie. red and white blood cells. This project concentrates on the processes by which these stem cells can achieve these two functions. What are the genes that enable a stem cell to have this self-renewal characteristic and conversely what are the genes that are activated when a cell becomes committed to become, for example, a white blood cell ? We have identified a gene, Pax5, which is essential in the process whereby a stem cell commits to become a lymphocyte . Our aim is to understand the function of Pax5 as a model for understanding how the commitment process as a whole works in the blood. These studies, as well as having an underlying fundamental scientific importance, are relevant to the clinical development of a number of stem cell therapies which rely on boosting stem cell production in procedures such as bone marrow transplantation for leukaemia and immune deficiency. In addition a number of characterised human blood malignancies indicate that inappropriate lineage commitment may be a factor in cancer.Read moreRead less
microRNA are non-coding RNAs with fundamental functions in biology and emerging roles in disease. Hundreds of microRNA have been found and they control gene expression by destroying RNA or controlling their translation into cellular proteins. We will characterise their mechanisms of action and the cellular factors that are involved. Understanding the way microRNA work is a key question in gene regulation research and will aid the development of therapeutic strategies invovling small RNA.
Probing The Cellular Functions Of The Translation Factor P97
Funder
National Health and Medical Research Council
Funding Amount
$370,307.00
Summary
The protein p97 takes part in the synthesis of cellular proteins from messenger RNA, a central step in gene expression. We will characterise p97 function as cells progress through their cycle of growth and division, and during responses to stress. Cellular stress is important in many diseases, such as viral infection, diabetes, heart disease, cancer, or complications during major surgery. Knowledge of p97 function may help us to better understand and treat these diseases.
Matching Between Codon Usage And TRNA Abundance Determines The Expression Of Targeting Genes In Mammalian Cells
Funder
National Health and Medical Research Council
Funding Amount
$358,500.00
Summary
This proposal is about optimal production of protein drugs (biopharmaceuticals), using genetic engineering in the laboratory and gene therapy in patients. It will explore the science behind a novel observation that the optimal way to use the genetic code to encode proteins for production varies from cell to cell in the lab, and from tissue to tissue in patients. If successful, a simple test can be used to decide the optimal genetic code for a specific application.
This is a study of the biological system of epigenetics. Every cell in our body has the same genetics, or library of information contained in the form of DNA sequence. Epigenetics is the system that controls how this DNA is used in a particular situation, or what books are opened and read. During embryonic development, cells know what they want to become, e.g., a muscle cell, and, once they take on an identity, remember that they are when they duplicate themselves during growth. Epigenetics does ....This is a study of the biological system of epigenetics. Every cell in our body has the same genetics, or library of information contained in the form of DNA sequence. Epigenetics is the system that controls how this DNA is used in a particular situation, or what books are opened and read. During embryonic development, cells know what they want to become, e.g., a muscle cell, and, once they take on an identity, remember that they are when they duplicate themselves during growth. Epigenetics does not achieve this through changing genetics the library always stays intact. Rather, it acts by using proteins or chemicals to make DNA functional in one way, or another. Genomic imprinting is a special type of epigenetics. While an embryo has received identical genetic information from each of its parents, the epigenetic information received from each parent was not entirely the same. Some genes which behave differently according to what parent they came from. For example, a gene that makes a growth factor protein is active only if received from the father. If received from the mother, it is inactive, and makes no protein. Genes behaving in this way are known as imprinted genes. We are trying to discover what epigenetic mechanisms are behind this behaviour of imprinted genes. One way we are approaching this problem is to study germ cells the cells giving rise to eggs and sperm. These cells are unusual in that their imprinted genes behave in the same way regardless of whether they were received from the mother or father, i.e., like any other gene. If we can understand why this is the case, we will be better able to understand why imprinted genes behave the way they do in the rest of the cells of the body. Broadly, the mechanisms we uncover should further our understanding of germ cell development, gene expression, and disease. Perturbations in the epigenetic profile are likely causes of human disease, including cancer.Read moreRead less
Marsupial germ cells and genes. Germ cells are the most fascinating cells in the body, since theirs is the unique responsibility for transmitting life from generation to generation. Studies in mice have suggested that position in the embryo determines their origin, but the early embryology of the mouse is so different from that of other mammals that the events need confirming and extending in another species. The simplified embryology of the tammar wallaby makes it ideal for studying one of the ....Marsupial germ cells and genes. Germ cells are the most fascinating cells in the body, since theirs is the unique responsibility for transmitting life from generation to generation. Studies in mice have suggested that position in the embryo determines their origin, but the early embryology of the mouse is so different from that of other mammals that the events need confirming and extending in another species. The simplified embryology of the tammar wallaby makes it ideal for studying one of the most fundamental questions in the whole of biology: what is the basis for the primal distinction between sex and soma?Read moreRead less
How does the unilaminar blastocyst form an embryo? Marsupials are synonymous with Australia and they are scientifically amazing. An understanding how the single-layered marsupial blastocyst cells are directed to form the complex organisation of an embryo would help us understand the biology underlying the developmental potential of all cells. Understanding these processes is not only of great fundamental interest to developmental biology but also for the development of embryonic stem cell lines. ....How does the unilaminar blastocyst form an embryo? Marsupials are synonymous with Australia and they are scientifically amazing. An understanding how the single-layered marsupial blastocyst cells are directed to form the complex organisation of an embryo would help us understand the biology underlying the developmental potential of all cells. Understanding these processes is not only of great fundamental interest to developmental biology but also for the development of embryonic stem cell lines. This research will continue Australia's high profile in reproductive biology using one of our iconic native mammals. A greater understanding of marsupial reproduction will also contribute to management of our threatened marsupial populations.Read moreRead less