Patient Toxicity Prediction: Identification Of Mucosal Injury Mediators Using Microarray Technology
Funder
National Health and Medical Research Council
Funding Amount
$292,639.00
Summary
There is no effective way to identify all patients that will develop toxic side-effects during the course of their cancer treatment. Current pharmacogenetic testing is too narrow. This project aims to examine whole-genome profiles of patient blood to determine if risk markers of toxicity can be identified prior to beginning treatment. I will do this by comparing oesophageal cancer patients who go on to develop severe toxicity with those who only get mild treatment side-effects.
Functional Analysis Of The P160 Myb-binding Protein - A Regulator Of Multiple Transcription Factors?
Funder
National Health and Medical Research Council
Funding Amount
$376,697.00
Summary
The c-myb gene is a key molecular regulator of normal blood cell production, but alterations to this gene can also lead to leukaemia. The protein (Myb) encode by the c-myb gene acts as a transcription factor, ie, it controls the activity of other genes. There is good evidence that interactions with other proteins can regulate the activity of Myb. Our laboratory has identified what we believe is one such protein - p160 - that binds to a part of Myb that reduces its activity, and thus that is like ....The c-myb gene is a key molecular regulator of normal blood cell production, but alterations to this gene can also lead to leukaemia. The protein (Myb) encode by the c-myb gene acts as a transcription factor, ie, it controls the activity of other genes. There is good evidence that interactions with other proteins can regulate the activity of Myb. Our laboratory has identified what we believe is one such protein - p160 - that binds to a part of Myb that reduces its activity, and thus that is likely to be responsible for regulating Myb. However, it has recently become apparent that p160 interacts with a number of other transcription factors in addition Myb. The primary aim of this project is to elucidate precisely how p160 interacts with Myb and what the consequences of this interaction are. A range of experimental approaches, which range from in vitro to genetic studies, will be employed to do this. We will test a specific role of p160 suggested by our preliminary studies - that of a transporter of transcription factors between the nucleus and the cytoplasm of the cell. Because of the wide range of transcription factors that p160 interacts with, its effects on the function of the cell are likely to be profound. For this same reason, it is difficult to specifically predict the possible medical-health implications of this work However, what we know to date is consistent with a role for p160 as a tumour suppressor gene. Moreover, parts of this project aim to generate genetic information and tools which will help in determining whether p160 does play such a role and generally, in identifying any other associations of p160 with particular diseases.Read moreRead less
Retrotransposons As Controlling Elements In Mammals: A Screen For Expression In Somatic Cells And Cancer
Funder
National Health and Medical Research Council
Funding Amount
$452,545.00
Summary
Differences between individual mammals are generally thought to be due to differences either between their genes, or between their environments. However, in many cases genetic or environmental factors cannot account for differences between individuals. We have studied mice in which dramatic differences between genetically identical individuals are due solely to the activity of a type of transposable element (transposon). There are tens of thousands of similar elements in the genomes of all mamma ....Differences between individual mammals are generally thought to be due to differences either between their genes, or between their environments. However, in many cases genetic or environmental factors cannot account for differences between individuals. We have studied mice in which dramatic differences between genetically identical individuals are due solely to the activity of a type of transposable element (transposon). There are tens of thousands of similar elements in the genomes of all mammals. A large body of evidence demonstrates that transposons can disrupt gene expression. To prevent this from occurring, most organisms have evolved mechanisms to keep transposons silent. However, fragmentary evidence indicates that transposons are at least sometimes expressed in normal and cancer cells. We hypothesize that activity of transposons in mammals alters gene expression sufficiently to cause variation between individuals, and that altered gene expression can cause disease (particularly cancer) and some manifestations of aging. As a first step toward testing this hypothesis, it is essential to acquire more complete information on the expression of transposons in normal and diseased cells. Furthermore, if transposon expression is closely linked to the development or progression of cancer or aging, then the ability to monitor such expression could have diagnostic utility. DNA array technology is coming into wide use to compare patterns of gene expression in different types of cells. We propose to adapt this method to the study of transposon expression. We will clone examples of all known classes of mouse and human transposon, and study transposon expression in: 1. Normal mice, at intervals from the earliest phase of development to old age, and 2. Human cancers of a variety of types. These studies will provide information of fundamental significance for mammalian biology, and also have the potential to lead to improved diagnosis of disease.Read moreRead less
Alternative Splicing Of GLI1 And Its Role In Tumourigenesis
Funder
National Health and Medical Research Council
Funding Amount
$392,640.00
Summary
Gene expression involves the transfer of information from DNA to proteins and is mediated by a third molecule called messenger RNA (mRNA). The process is tightly controlled since unregulated gene expression is harmful and can result in diseases such as developmental disorders and cancer. The genetic information in DNA is first copied to an RNA molecule in a process called transcription. This RNA molecule then undergoes a series of maturation steps before the information it carries can be transla ....Gene expression involves the transfer of information from DNA to proteins and is mediated by a third molecule called messenger RNA (mRNA). The process is tightly controlled since unregulated gene expression is harmful and can result in diseases such as developmental disorders and cancer. The genetic information in DNA is first copied to an RNA molecule in a process called transcription. This RNA molecule then undergoes a series of maturation steps before the information it carries can be translated into a protein. One of these maturation steps involves the removal of sequences (called introns) that do not contain protein coding information from the sequences (called exons) that will be present in the mature mRNA. Some genes contain no introns while others contain 20 or more, which are dispersed throughout the gene. The removal of intron sequences from immature RNA molecules is called splicing and is carried out by a macromolecular complex that recognises the intron sequences, cuts them out of the RNA and then rejoins the RNA to make a contiguous sequence. This process has to be precise otherwise spurious sequences will be present in the mRNA, which will result in the production of abnormal proteins. In addition, for some genes mRNAs are produced that have differences in a portion of their sequence. These alternative sequences are generated by the inclusion or exclusion of alternative exons. Because, RNA splicing is critical to the production of mature mRNAs and because it can generate sequence diversity it is tightly regulated. We have recently found that expression of a cancer gene (called GLI1) is regulated in part by the use of alternative GLI1 mRNAs. Moreover, we found that the expression of one of these alternative GLI1 mRNAs is associated with skin cancer. In this project we will investigate the molecular mechanisms that regulate alternative splicing in GLI1 and identify whether changes in these mechanisms result in cancer.Read moreRead less
Variable Expressivity And Epigenetic Inheritance At The Axin Fused Locus In The Mouse
Funder
National Health and Medical Research Council
Funding Amount
$242,545.00
Summary
Genes influence the way we look and variations in gene sequence can account for the differences between individuals. Family traits are often credited to gene variants that are passed down through generations of families. There is now intriguing evidence, some coming from our laboratory, that gene sequence is not the only thing we inherit from our parents. Modifications that alter the expression but not the sequence of a gene, known as epigenetic modifications can, it turns out, be inherited in m ....Genes influence the way we look and variations in gene sequence can account for the differences between individuals. Family traits are often credited to gene variants that are passed down through generations of families. There is now intriguing evidence, some coming from our laboratory, that gene sequence is not the only thing we inherit from our parents. Modifications that alter the expression but not the sequence of a gene, known as epigenetic modifications can, it turns out, be inherited in mammals. An epigenetic modification is a mark, present on some genes that determines whether the gene is expressed (switched on) or silent. Animals are thought to acquire this mark during development and it is retained throughout life except in germ cells where the mark is generally, but not always, erased. The establishment of the mark appears to be a stochastic event at the cellular level resulting in mosaic expression. The percentage of marked cells can differ from one individual to another . In theory, this could help to explain why individuals with identical genetic information, such as identical twins, can have different phenotypic characteristics. The fact that these modifications can be inherited implies that there is an alternative mode of inheritance of genetic traits which does not involve mutation but which can be carried from generation to generation in a semipermanent way. Understanding the mechanisms underlying these events is important if we wish to predict or modify the phenotype of an invidual or that of his or her offspring.Read moreRead less
Identification Of Variably Expressed Genes In Isogenic Mice And Humans
Funder
National Health and Medical Research Council
Funding Amount
$293,080.00
Summary
Monozygotic twins are known to have different phenotypic characteristics even though they contain identical genetic information. It is not uncommon for identical twins to have different coloured eyes and to show discordance for genetic diseases. While there is no definitive explanation for these differences they are generally thought to be caused by subtle changes in environmental conditions. We believe however, that these differences are set up during early embryonic development by the establis ....Monozygotic twins are known to have different phenotypic characteristics even though they contain identical genetic information. It is not uncommon for identical twins to have different coloured eyes and to show discordance for genetic diseases. While there is no definitive explanation for these differences they are generally thought to be caused by subtle changes in environmental conditions. We believe however, that these differences are set up during early embryonic development by the establishment of epigenetic modifications to the DNA. An epigenetic modification is a mark which determines whether a gene is expressed (switched on) or silent (switched off). The establishment of the mark appears to be a stochastic event which can result in different physical characteristics between genetically identical individuals. We would like to study this process in inbred mouse strains and in humans. Inbred mouse strains are maintained by inbreeding (brother-sister mating) to ensure that all individuals of the strain are isogenic (genetically identical) and in such a way that environmental variation is minimised. We will use established molecular techniques to find genes which are variably expressed among isogenic mice and humans. This work will enable us to discover genes which are sensitive to epigenetic modifications and whose epigenotype must be known if we are able to predict phenotype or disease state.Read moreRead less
Adaptive Evolution of BRCA1 in Ancestral Mammals. This project investigates adaptive evolution of BRCA1 in the early radiation of mammals. We will test the hypothesis that the evolution of mammary glands and X chromosome inactivation has resulted in modification of the BRCA1 protein sequence as it aquired new roles in these processes. We will also investigate the importance of these changes inducing compensatory changes in other parts of the protein.
Discovery of novel microRNA biogenesis and functional components. Discovery of novel microRNA components will provide new strategies for confronting a diverse array of challenges Australia faces, such as the increasing rates of certain cancers in our population, to stresses on our crop plants faced with environmental changes. The biological mechanisms underlying these disparate problems are unified by microRNA involvement in many instances. By finding microRNA controlling factors common to all h ....Discovery of novel microRNA biogenesis and functional components. Discovery of novel microRNA components will provide new strategies for confronting a diverse array of challenges Australia faces, such as the increasing rates of certain cancers in our population, to stresses on our crop plants faced with environmental changes. The biological mechanisms underlying these disparate problems are unified by microRNA involvement in many instances. By finding microRNA controlling factors common to all higher organisms, we expect our community will benefit from the increased knowledge base that will help our researchers adopt new strategies in fighting diseases and improving our agricultural industry.Read moreRead less
The Establishment Of Epigenetic Marks At Metastable Epialleles In The Mouse
Funder
National Health and Medical Research Council
Funding Amount
$372,750.00
Summary
Occasionally, identical twins are found to have distinctly different characteristics, such as eye colour or severity of genetic disease, that clearly cannot be explained by their genetic makeup, and are unlikely to be the result of environmental differences. In genetically identical mice, similar cases exist, where some mice have a yellow coat and others a brown coat. In instances such as these, a growing body of evidence suggests that certain modifications to genes are responsible. These modifi ....Occasionally, identical twins are found to have distinctly different characteristics, such as eye colour or severity of genetic disease, that clearly cannot be explained by their genetic makeup, and are unlikely to be the result of environmental differences. In genetically identical mice, similar cases exist, where some mice have a yellow coat and others a brown coat. In instances such as these, a growing body of evidence suggests that certain modifications to genes are responsible. These modifications are not traditional DNA mutations, but are chemical modifications of the basic sequence. Currently, we do not know when these DNA modifications are established during foetal development. We will use the mouse coat colour gene mentioned above to investigate when the different physical characteristics are established in embryonic development. Indeed, there is increasing evidence that critical periods exist in human foetal development where minor environmental or nutritional changes can affect long-term health of the adult. Perhaps the establishment of the DNA modifications are under an environmental or nutritional influence. Further study of when and how the DNA modifications are set-up during embryonic development is necessary in order to understand these events.Read moreRead less
Transcriptional and epigenetic regulation of terminal lymphocyte differentiation and alterations of the same that lead to leukemia. In the developed world infection diseases are the number three killer behind heart disease and cancer, and huge financial effort is put into treatment and prevention. Despite this, results have often been disappointing. One cause of these poor outcomes is the lack of knowledge of how effective immune responses are generated. This project aims to better understand th ....Transcriptional and epigenetic regulation of terminal lymphocyte differentiation and alterations of the same that lead to leukemia. In the developed world infection diseases are the number three killer behind heart disease and cancer, and huge financial effort is put into treatment and prevention. Despite this, results have often been disappointing. One cause of these poor outcomes is the lack of knowledge of how effective immune responses are generated. This project aims to better understand the processes that control the generation of protective lymphocytes. It will deliver information that may enable a more targeted approach to vaccine-development and treatments of infections. As defective differentiation can also be a cause of leukemia it may also lead to targets of cancer treatment.Read moreRead less