Alternate Splicing Of Tryptase Genes Regulates Their Specificity
Funder
National Health and Medical Research Council
Funding Amount
$294,250.00
Summary
Tryptases are enzymes implicated in inflammatory disorders including arthritis, inflammatory bowel disease (IBD) and asthma. Specific tryptase inhibitors are effective in treating these diseases. We have discovered that each human tryptase gene is processed into two different protein products via a mechanism called alternate splicing. We will investigate the structure and function of these.
Genomic Characterisation Of Novel Inflammatory Regulators In A Mouse Model Of Disseminated Candidiasis
Funder
National Health and Medical Research Council
Funding Amount
$581,427.00
Summary
Genome biology offers great promise for the study of immune function, but new approaches are needed to build insights between data and disease. This project looks at the gene products used by mice susceptible to yeast infection and asks if the information is used differently in resistant animals. Blood-borne fungal infections are increasing in hospitals; we want to discover new immune gene products and understand how they contribute, so we can better predict the outcome of an infection.
Distribution Kinetics Of Opioids Used In Substitution Programs
Funder
National Health and Medical Research Council
Funding Amount
$196,527.00
Summary
Heroin addiction is a major national and international problem costing hundreds of millons of dollars to Australia alone. The major form of treatment is methadone taken as maintenance treatment once a day. While methadone is effective in most addicts, about one third of them complain that it does not last long enough and they either tolerate this inadequate form of treatment or are prescribed a newer drug as part of a clinical trial or drop out and revert to heroin. We have previously shown that ....Heroin addiction is a major national and international problem costing hundreds of millons of dollars to Australia alone. The major form of treatment is methadone taken as maintenance treatment once a day. While methadone is effective in most addicts, about one third of them complain that it does not last long enough and they either tolerate this inadequate form of treatment or are prescribed a newer drug as part of a clinical trial or drop out and revert to heroin. We have previously shown that the blood levels of methadone are important in determining its best use and specifically, that those addicts for whom methadone does not hold have a greater drop in their blood levels after methadone has been absorbed into the body. This drop in blood levels is mainly due to methadone's redistribution throughout the body. Very little is known about how methadone distributes and redistributes throughout the body but it appears that the lung is the most important organ. A number of questions need to be answered to improve methadone's use: 1. How quickly is methadone taken up into the lung compared to the brain; 2. Why is the lung able to take up and release a large amount of methadone; 3. How does decreased respiration influence the lung and brain uptake of methadone; 4. What happens when another drug is prescribed (such as an antidepressant) which reduces the lung uptake of methadone; 5. Do some of the newer drugs for heroin addiction have better lung distribution and binding properties. We will perform studies of the concentrations of methadone and newer drugs in sheep that will provide the scientific basis for answering these questions and permit better use of drug treatment for heroin addiction.Read moreRead less
Structure And Function Of The Alternative Splicing Factor ZNF265
Funder
National Health and Medical Research Council
Funding Amount
$509,017.00
Summary
Now that the human genome has been sequenced, we can see that a human being is defined bye approximately 30000 genes. One of the biggest surprises to come from this work was that the number of genes was significantly smaller than many predicted. Similar surprise was registered at the discovery that the genome of the fruit fly actually contained fewer genes than that of the model worm, Caenorhabditis elegans. Part of the explanation for these apparent discrepencies lies in the phenomenon known as ....Now that the human genome has been sequenced, we can see that a human being is defined bye approximately 30000 genes. One of the biggest surprises to come from this work was that the number of genes was significantly smaller than many predicted. Similar surprise was registered at the discovery that the genome of the fruit fly actually contained fewer genes than that of the model worm, Caenorhabditis elegans. Part of the explanation for these apparent discrepencies lies in the phenomenon known as gene splicing, whereby one gene can actually give rise to many different isoforms of the same protein. These different isoforms can have different structures and-or functions, and dramatically increase the complexity that it is possible for an organism to achieve with a given number of genes. The process of splicing is very intricate, requiring precise control to allow an organism to develop normally. Many human genetic diseases are known to arise from problems with splicing. However, our understanding of the mechanisms of splicing is rather incomplete. This proposal aims to improve our understanding of the splicing process through a range of biophysical and molecular biological approaches. This information should prove useful in understanding human development and disease.Read moreRead less
Therapeutic Induction Of Dytrophin-positive Revertant Fibres In The Mdx Mouse
Funder
National Health and Medical Research Council
Funding Amount
$454,825.00
Summary
Revertant fibres are low-abundance, dystrophin-positive fibres found in muscle of DMD patients and animal models. These fibres appear to have a selective advantage over dystrophin negative fibres, as they accumulate with age. Characterisation of dystrophin mRNA has identified in-frame transcripts missing multiple exons, which either exclude a nonsense mutation or restore the reading frame around a deletion. We have designed antisense oligonucleotides (AOs) to bind regions flanking the exon conta ....Revertant fibres are low-abundance, dystrophin-positive fibres found in muscle of DMD patients and animal models. These fibres appear to have a selective advantage over dystrophin negative fibres, as they accumulate with age. Characterisation of dystrophin mRNA has identified in-frame transcripts missing multiple exons, which either exclude a nonsense mutation or restore the reading frame around a deletion. We have designed antisense oligonucleotides (AOs) to bind regions flanking the exon containing the dystrophin mutation in the mdx mouse. The AOs interfere with processing of the pre-mRNA to exclude the mutation and allow a slightly shortened dystrophin to be synthesised. The use of AOs to modify RNA processing allows the gene to function under the control of natural regulatory elements. We have shown that AOs can induce dystrophin expression and improve strength in dystrophic (mdx) mouse hindlimb muscles. We aim to improve upon these results by using AOs to block splice sites flanking consecutive exons, in order to induce dystrophin which mimics that of revertant fibres. As most revertant transcripts are missing multiple exons, we believe that the functional capacity of AO-induced dystrophin can be improved upon by removing multiple exons. An mdx mouse skeletal muscle cell line is used for evaluation AOs. However, in order to determine the efficacy of the induced dystrophin in cardiac and skeletal muscle, experiments must be performed on mice. Previous work, in vitro and in muscles of mdx mice have validated this approach. Combinations of AOs which show promise will be delivered by a) intravascular injection b) intraperitoneal injection in mdx mice. The efficacy of the treatment will be assessed by both continual and end point analysis, which includes physiological, clinical, molecular and histological testing. Particular attention will be directed to the well-being of the mice and any adverse side effects which may occur.Read moreRead less