Articles by Daniel Ong in JoVE
Regular Care and Maintenance of a Zebrafish (Danio rerio) Laboratory: An Introduction Avdesh Avdesh*1,2, Mengqi Chen*1,3, Mathew T. Martin-Iverson1,2,4, Alinda Mondal1,3, Daniel Ong1, Stephanie Rainey-Smith1,3, Kevin Taddei1,3, Michael Lardelli5, David M. Groth6, Giuseppe Verdile1,3, Ralph N. Martins1,2,3,7 1Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical sciences, Edith Cowan University, 2Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, University of Western Australia, 3McCusker Alzheimer's Research foundation, 4School of Medicine and Pharmacology, University of Western Australia, 5Department of Molecular and Biomedical Sciences, University of Adelaide, 6School of Biomedical Sciences, Curtin University of Technology, 7School of Psychiatry and Clinical Neurosciences, University of Western Australia This protocol outlines regular maintenance and care to maintain optimal conditions for zebrafish husbandry. The video illustrates the protocol for system maintenance, regular housing, feeding, breeding, and raising of zebrafish larvae.
Other articles by Daniel Ong on PubMed
Zinc Transport Activity of Fear of Intimacy is Essential for Proper Gonad Morphogenesis and DE-cadherin Expression Development (Cambridge, England). Mar, 2006 | Pubmed ID: 16481356 Embryonic gonad formation involves intimate contact between germ cells and specialized somatic cells along with the complex morphogenetic movements necessary to create proper gonad architecture. Previously, we have shown that gonad formation in Drosophila requires the homophilic cell-adhesion molecule Drosophila E-cadherin (DE-cadherin), and also Fear of Intimacy (FOI), which is required for stable accumulation of DE-cadherin protein in the gonad. Here, we present an in vivo structure-function analysis of FOI that strongly indicates that zinc transport activity of FOI is essential for gonad development. Mutant forms of FOI that are defective for zinc transport also fail to rescue morphogenesis and DE-cadherin expression in the gonad. We further show that expression of DE-cadherin in the gonad is regulated post-transcriptionally and that foi affects this post-transcriptional control. Expression of DE-cadherin from a ubiquitous (tubulin) promoter still results in gonad-specific accumulation of DE-cadherin, which is strongly reduced in foi mutants. This work indicates that zinc is a crucial regulator of developmental processes and can affect DE-cadherin expression on multiple levels.
Extracellular Cholesterol-rich Microdomains Generated by Human Macrophages and Their Potential Function in Reverse Cholesterol Transport Journal of Lipid Research. Aug, 2010 | Pubmed ID: 20421591 Previous studies have shown that cholesterol in atherosclerotic plaques is present in both intracellular and extracellular forms. In the current study, we investigated a mechanism for extracellular cholesterol accumulation and examined the capacity of this pool of cholesterol to be removed by cholesterol acceptors, a step in reverse cholesterol transport. Human monocyte-derived macrophages differentiated with macrophage-colony stimulating factor were incubated with acetylated LDL to allow cholesterol enrichment and processing. These macrophages were subsequently labeled with a monoclonal antibody that specifically detects ordered cholesterol arrays, revealing the presence of unesterified cholesterol-rich microdomains on the cell surfaces and in the extracellular matrix. Similar unesterified cholesterol-rich microdomains were present in human atherosclerotic plaques. Actin microfilaments functioned in microdomain deposition or maintenance, and Src family kinases regulated transfer of these microdomains from the cell surface onto the extracellular matrix. Mediators of reverse cholesterol transport, apolipoprotein A-I (apoA-I), and HDL were capable of removing these extracellular un-esterified cholesterol-rich microdomains. However, apoA-I removed the microdomains only when macrophages were present. ApoA-I removal of microdomains was blocked by glyburide and inhibitor of ATP-binding cassette transporter A1 (ABCA1) function. In summary, cultures of cholesterol-enriched human monocyte-derived macrophages generate extracellular unesterified cholesterol-rich microdomains, which can subsequently be removed by cholesterol acceptors and therefore potentially function in reverse cholesterol transport.
Size and Shape of the Caudate Nucleus in Individuals with Bipolar Affective Disorder The Australian and New Zealand Journal of Psychiatry. Apr, 2012 | Pubmed ID: 22368240 The caudate nucleus (CN) is a crucial component of the ventral striatum, which is part of a prefrontal-striatal-thalamic circuit that is modulated by limbic structures to subserve emotional processing. Bipolar disorder is thought to be underpinned by dysfunctional anterior limbic networks, although MRI studies examining the CN have shown equivocal results. As gross volumetric analyses may not detect subtle regional change, we aimed to clarify the role of the CN in bipolar disorder by undertaking shape analysis to detect regional reductions.