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Dear GRC: As most of you are aware, the online ranavirus course being coordinated by the GRC is underway. There are 46 participants (2/3 students, 1/3 professionals) from 7 countries spanning various disciplines (ecology, conservation, natural resources, veterinary medicine, microbiology, zoological, education)! Currently, 6 April 2016 is saved as "Open Topics." The GRC Board decided to use this date as a contemporary topics session, where unpublished results on ranaviruses will be delivered from 8 speakers (students or professionals). Twenty minutes will be allotted for each presentation. If you are interested in presenting, please submit a <300-word abstract to Amanda Duffus ([log in to unmask]), and cc: Jesse Brunner ([log in to unmask]) and me ([log in to unmask]) by 9 March 2016. The presentations will be delivered using Zoom (it is similar to Skype but more powerful), so there is no need to travel - you can deliver the presentation from your office or home (Internet connection is required). Presentations need to be delivered in real-time on 6 April; the class meets from 9:05 - 12:05 Eastern Time (New York), USA. Below is an example format for abstract submission. If you have any questions, please let us know. All the Best, Matt =================================================== The three dimensional structure and morphogenesis of Singapore grouper iridovirus B. Tran1, D-H. Chen2, Y. Liu1, J. Wu3, C. Wah2, and C. Hew1, 3 1Mechanobiology Institute Singapore, National University of Singapore, Singapore. 2Baylor College of Medicine, Houston, TX, USA. 3Department of Biological Sciences, National University of Singapore, Singapore. Singapore grouper iridovirus (SGIV), a major pathogen in grouper aquaculture, was first isolated in 1998 from brown-spotted grouper. In the past decade, we carried out the viral genomic, transcriptomic, proteomic and lipidomic studies, dissected its molecular compositions and revealed its gene expression profiles. Our results show that the complex virion contains a dsDNA genome of 140,131 bp, at least 44 structural proteins and 220 lipid species. How these molecules are assembled to form a viral particle is unknown. Recent advances in cryoEM/ET technology and computational power have made it possible to examine the structure and morphogenesis of large complex viruses in three dimensions. We took more than 1000 frames with an FEI Titan Krios microscope and selected about 6000 particles for 3D reconstruction. A subnano resolution map was obtained, which reveals: 1) hexamers and pentamers distributed on a T = 247 icosahedral lattice; 2) an irregular lipid bilayer between the capsid shell and viral core; 3) anchor proteins located between the capsid shell and the inner lipid bilayer. High-pressure freezing and freeze substitution were used to prepare SGIV-infected cells for electron microscopy. The viral capsid precursors first appear as closed membrane structures, then develop into headphone shape structures and capsid shells. We identified viral intermediates showing that the viral DNA is packaged into viral capsid during capsid formation. Knockdown of MCP disrupts the viral morphogenesis and diminishes the production of viral particles, while knockdown of viral DNA core protein leads to reduction of viral titer and deformities in viral particles. ______________________________________________________________ Matthew J. Gray, Ph.D., Professor Director, Global Ranavirus Consortium<http://www.ranavirus.org/> Co-chair, PARC National Disease Task Team<http://www.parcplace.org/parcplace/resources/disease-task-team.html> Associate Director, Center for Wildlife Health ORU University of Tennessee 274 Ellington Plant Sciences Building Knoxville, TN 37996-4563 865.974.2740 [ofc] [log in to unmask]<mailto:[log in to unmask]> 865.974.4714 [fax] http://fwf.ag.utk.edu/personnel/mgray.htm For more information about Forestry, Wildlife and Fisheries at UTK, Please visit http://fwf.ag.utk.edu/ or call 865.974.7126 _____________________________________________________________