microRNAs: discovery and analysis in mouse development. MicroRNAs (miRNAs) are a new class of regulatory molecule, recently found to be abundant and strongly conserved in several eukaryotic species, encoded by genes that are transcribed into short stem-loop structures and then processed into ~22nt single-stranded RNAs by the RNAi pathway. We have cloned novel miRNAs, and obtained the first evidence for regulation of a miRNA in a mammal. We propose to continue cloning novel miRNAs by the tried m ....microRNAs: discovery and analysis in mouse development. MicroRNAs (miRNAs) are a new class of regulatory molecule, recently found to be abundant and strongly conserved in several eukaryotic species, encoded by genes that are transcribed into short stem-loop structures and then processed into ~22nt single-stranded RNAs by the RNAi pathway. We have cloned novel miRNAs, and obtained the first evidence for regulation of a miRNA in a mammal. We propose to continue cloning novel miRNAs by the tried method, and to explore bioinformatics-based methods of identification. We will also study the expression of miRNAs in mouse embryos at successive stages, and develop a microarray assay for miRNA expression.Read moreRead less
Progenitor cells within the peritoneal cavity. Implantation of a foreign object into the peritoneal cavity of animals recruits undifferentiated cells of bone marrow origin that encapsulate the free-floating object, then differentiate into myofibroblasts. When large pieces of myofibroblast capsule tissue are subsequently grafted into autologous artery, bladder or vas deferens, they develop the structure and morphology of that organ. We hypothesise that multipotent progenitor cells sequestered t ....Progenitor cells within the peritoneal cavity. Implantation of a foreign object into the peritoneal cavity of animals recruits undifferentiated cells of bone marrow origin that encapsulate the free-floating object, then differentiate into myofibroblasts. When large pieces of myofibroblast capsule tissue are subsequently grafted into autologous artery, bladder or vas deferens, they develop the structure and morphology of that organ. We hypothesise that multipotent progenitor cells sequestered to the peritoneal cavity can be manipulated to differentiate along smooth muscle and other pathways. The proposed project aims to identify the origin of these cells and characterise the transcriptional program that regulates their differentiation.Read moreRead less
Tissue specific regulation of gene expression. Despite the polarized public debate concerning the use of stem cells for tissue regeneration, fundamental questions relating to the identity and hierarchy of these cells remain unanswered. The benefit to Australia will be scientific in terms of providing an understanding of how stem and progenitor cells integrate transcriptional control systems during differentiation and the networks that are involved. This is fundamental to the future isolation a ....Tissue specific regulation of gene expression. Despite the polarized public debate concerning the use of stem cells for tissue regeneration, fundamental questions relating to the identity and hierarchy of these cells remain unanswered. The benefit to Australia will be scientific in terms of providing an understanding of how stem and progenitor cells integrate transcriptional control systems during differentiation and the networks that are involved. This is fundamental to the future isolation and manipulation of these stem cell types to benefit the community. The work will also provide postgraduate students with training in state of the art genomic techniques and in the interface between bioinformatics and experimental science. Read moreRead less
Single Minded 2: Cross coupling or specificity within the bHLH/PAS transcription factor family? Understanding the mechanisms of action of SIM2 may lead to novel ideas towards drug development for diseases such as Down syndrome and cancer. The SIM2 protein can interfere with activity of the related Hypoxia Inducible Factor (HIF), a protein important in stress response and recovery from stroke. Understanding the molecular basis of this interference could aid current strategies being used to manipu ....Single Minded 2: Cross coupling or specificity within the bHLH/PAS transcription factor family? Understanding the mechanisms of action of SIM2 may lead to novel ideas towards drug development for diseases such as Down syndrome and cancer. The SIM2 protein can interfere with activity of the related Hypoxia Inducible Factor (HIF), a protein important in stress response and recovery from stroke. Understanding the molecular basis of this interference could aid current strategies being used to manipulate HIF for pharmaceutical benefit.Read moreRead less
Transcriptional regulation of erythropoiesis. The major expected outcome from this proposal will be development of a pipeline for the study of how transcription factors work at a genome level. There will be national benefit in the areas of Frontier Technologies, and Promoting and Maintaining Good Health. There will be specific outcomes with respect to development of tests for human blood diseases, future design of drugs to target the aberrant activities of transcription factors in genetic and de ....Transcriptional regulation of erythropoiesis. The major expected outcome from this proposal will be development of a pipeline for the study of how transcription factors work at a genome level. There will be national benefit in the areas of Frontier Technologies, and Promoting and Maintaining Good Health. There will be specific outcomes with respect to development of tests for human blood diseases, future design of drugs to target the aberrant activities of transcription factors in genetic and degenerative diseases. Also, a strong bridge will be built upon the previous collaborations of the research teams in Brisbane and Pennsylvania, which will facilitate advanced teaching and training of Australian PhD and post-doctoral scientists.Read moreRead less
Exploration of a mechanistic link between eukaryotic transcription and translation. Gene transcription is functionally coupled to other aspects of eukaryotic mRNA metabolism, emphasizing a need for integrated approaches to analyse the gene expression pathway. We have shown in previous work that yeast cells, when responding to external stimuli, show a tight correlation between changes in the transcriptome composition and homodirectional alterations in the translation state of mRNAs. This phenomen ....Exploration of a mechanistic link between eukaryotic transcription and translation. Gene transcription is functionally coupled to other aspects of eukaryotic mRNA metabolism, emphasizing a need for integrated approaches to analyse the gene expression pathway. We have shown in previous work that yeast cells, when responding to external stimuli, show a tight correlation between changes in the transcriptome composition and homodirectional alterations in the translation state of mRNAs. This phenomenon of ?potentiation? may serve to amplify signal-induced changes in the transcriptome at the translational level. This project will begin to unravel the molecular mechanisms underlying potentiation using experiments designed to distinguish between transcription- and translation-driven mechanisms.Read moreRead less
The sulfate anion transporter gene, Sat1: physiology, regulation and developmental expression. Sulfate is an essential nutrient for cell growth and survival. The kidneys and liver help regulate sulfate levels in the body, by yet unknown mechanisms. Recently, we cloned a gene, Sat1, expressed in mouse liver and kidneys, which may be responsible for body sulfate maintenance. In this study, we will determine the physiological importance of Sat1 in cell growth/survival and in controlling body sulfa ....The sulfate anion transporter gene, Sat1: physiology, regulation and developmental expression. Sulfate is an essential nutrient for cell growth and survival. The kidneys and liver help regulate sulfate levels in the body, by yet unknown mechanisms. Recently, we cloned a gene, Sat1, expressed in mouse liver and kidneys, which may be responsible for body sulfate maintenance. In this study, we will determine the physiological importance of Sat1 in cell growth/survival and in controlling body sulfate levels. We will generate and characterise a Sat1 lacking mouse, study its expression during development and its effects on other genes. We will elucidate how body sulfate levels are maintained and its importance in cell growth/development.Read moreRead less
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