Cooperative Research Centre

About: Cooperative Research Centre is a based out in . It is known for research contribution in the topics: Population & Sea ice. The organization has 7633 authors who have published 8607 publications receiving 429721 citations.

Novel genes regulated by Sonic Hedgehog in pluripotent mesenchymal cells.

Abstract: Sonic Hedgehog is a secreted morphogen involved in patterning a wide range of structures in the developing embryo. Disruption of the Hedgehog signalling cascade leads to a number of developmental disorders and plays a key role in the formation of a range of human cancers. The identification of genes regulated by Hedgehog is crucial to understanding how disruption of this pathway leads to neoplastic transformation. We have used a Sonic Hedgehog (Shh) responsive mouse cell line, C3H/10T1/2, to provide a model system for hedgehog target gene discovery. Following activation of cell cultures with Shh, RNA was used to interrogate microarrays to investigate downstream transcriptional consequences of hedgehog stimulation. As a result 11 target genes have been identified, seven of which are induced (Thrombomodulin, GILZ, BF-2, Nr4a1, IGF2, PMP22, LASP1) and four of which are repressed (SFRP-1, SFRP-2, Mip1-gamma, Amh) by Shh. These targets have a diverse range of putative functions and include transcriptional regulators and molecules known to be involved in regulating cell growth or apoptosis. The corroboration of genes previously implicated in hedgehog signalling, along with the finding of novel targets, demonstrates both the validity and power of the C3H/10T1/2 system for Shh target gene discovery.

Evaluating the Feasibility of Eradicating an Invasion

Abstract: The detectability of invasive organisms influences the costs and benefits of alternative control strategies, and the feasibility of eradicating an infestation. Search theory offers a mathematically rigorous framework for defining and measuring detectability taking account of searcher ability, biological factors and the search environment. In this paper, invasive species detectability is incorporated into a population simulation model. The model is applied to a base set of parameter values that represent reasonable values for a hypothetical weed. The analysis shows the effects of detectability and search effort on the duration of an eradication program. For a given level of detectability and search time, the analysis shows that the variables with the greatest influence on the duration of the eradication effort are search speed, kill efficiency, germination rate and seed longevity. Monte Carlo simulations are performed on a set of four weed scenarios, involving different combinations of plant longevity, seed longevity and plant fecundity. Results of these simulations are presented as probability distributions and allow us to calculate how the probability of eradication will be affected by search strategy.

Tracking of marine predators to protect Southern Ocean ecosystems

Abstract: Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally important region and assess current threats and protection levels. Integration of more than 4,000 tracks from 17 bird and mammal species reveals AESs around sub-Antarctic islands in the Atlantic and Indian Oceans and over the Antarctic continental shelf. Fishing pressure is disproportionately concentrated inside AESs, and climate change over the next century is predicted to impose pressure on these areas, particularly around the Antarctic continent. At present, 7.1% of the ocean south of 40°S is under formal protection, including 29% of the total AESs. The establishment and regular revision of networks of protection that encompass AESs are needed to provide long-term mitigation of growing pressures on Southern Ocean ecosystems.

Genetics of complex traits: prediction of phenotype, identification of causal polymorphisms and genetic architecture

Abstract: Complex or quantitative traits are important in medicine, agriculture and evolution, yet, until recently, few of the polymorphisms that cause variation in these traits were known. Genome-wide association studies (GWAS), based on the ability to assay thousands of single nucleotide polymorphisms (SNPs), have revolutionized our understanding of the genetics of complex traits. We advocate the analysis of GWAS data by a statistical method that fits all SNP effects simultaneously, assuming that these effects are drawn from a prior distribution. We illustrate how this method can be used to predict future phenotypes, to map and identify the causal mutations, and to study the genetic architecture of complex traits. The genetic architecture of complex traits is even more complex than previously thought: in almost every trait studied there are thousands of polymorphisms that explain genetic variation. Methods of predicting future phenotypes, collectively known as genomic selection or genomic prediction, have been widely adopted in livestock and crop breeding, leading to increased rates of genetic improvement.

Functional Relationships of Soil Acidification, Liming, and Greenhouse Gas Flux

Abstract: Soil acidification can be accelerated by intensive farming or prevented by sustainable management practices. Soil acidification in a managed agricultural production system is caused by the transformation of carbon (C), nitrogen (N), and sulfur (S), which releases protons (H+) to soil solution. Soil acidification decreases soil pH, causing adverse effects on plants and soil microorganisms. Acidification, coupled with aluminum, manganese, and iron toxicities, and phosphorus, calcium, magnesium, and potassium deficiencies, can lead to low soil fertility. Soil acidity influences soil C and N cycles by controlling activities of microorganisms involved in the transformations of these two elements. Traditionally, lime materials are added to neutralize acidic soils and to overcome the problems associated with soil acidification, but they also influence C and N cycles, thereby affecting greenhouse gas (GHG) flux in soils. For example, liming has been shown to decrease nitrification-induced nitrous oxide (N2O) emission from many agricultural lands. However, there are concerns that liming increases the availability of soil nitrate ( N O 3 − ), which is a substrate for N2O emission through denitrification. The dissolution of liming materials can act as either a net source or sink for carbon dioxide (CO2). Lime-derived CO2 reacts with microbial respiration-derived carbonic acid in soils to yield carbonate material, serving as a sink of CO2 in soil. In calcareous soils with high pH, agricultural lime (CaCO3) serves as a net sink for CO2 whereas in acid soils it serves as a net source of CO2. In acid soils, increased availability of aluminum (Al3+) ions inhibits activity of methane (CH4) oxidizers. Adding lime to soils has shown to increase CH4 oxidation and reduce GHG emission. The present review brings together basic concepts of soil acidification and recent developments on the implications of liming in relation to C and N transformations and cycling, particularly GHG emissions from soils. Given the major influence of lime addition on soil microorganisms relating to C and N cycles, future research should focus on the role of liming on soil microbial communities to provide insight into combined mitigation of N2O, CO2, and CH4 gases from agricultural soils.