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V Iral Evolution 4 Viral evolution Molecular evidence for evolution 4: Viral evolution | sr0299 teachers guide Molecular evidence for evolution 4: Viral evolution photo by AJ Cann Components NAME DESCRIPTION AUDIENCE Viral evolution This guide explains how to use bioinformatics tools teachers within the Influenza Research Database to build students’ teachers guide understanding of molecular evidence for evolution. Influenza This background sheet for teachers describes the structure teachers and reproduction of influenza viruses. background sheet Investigating influenza This background sheet for teachers describes how influenza teachers viruses evolve and mechanisms of antigenic drift and background sheet shift. It provides an introduction to bioinformatics and the Influenza Research Database. Fighting the ‘flu This factsheet describes the structure of influenza viruses students and how they evolve through antigenic shift and drift. fact sheet Influenza – an evolving This activity sheet guides students through interactive use students problem! of the Influenza Research Database. worksheet Purpose Outcomes Students develop an understanding of how databases Students understand that: may be used to map changes in influenza viruses as • there are different types of influenza virus that they evolve. affect different animal species; • evolution can occur rapidly in viruses, through mechanisms of antigenic drift and antigenic shift; • mutations or changes in nucleotide sequences of viruses mean hosts may not recognise a virus; and • online databases, such as the Influenza Research Database, enable scientists to track strains of viruses and map evolutionary changes, as they occur. Activity summary ACTIVITY POSSIBLE STRATEGY Students read the fact sheet, Fighting the ‘flu, to provide background individually or in pairs information for an online database activity. Students work through the activity, Influenza – an evolving problem!, individually or in pairs answering questions. ast1009 | Molecular evidence for evolution 4: Viral evolution (teachers guide) developed for the Department of Education WA © The University of Western Australia 2012 for conditions of use see spice.wa.edu.au/usage version 0.1 page 1 Licensed for NEALS Teacher notes on the Influenza Acknowledgements Research Database Grateful thanks are extended to Yun Zhang, Burke Squires, Brett Pickett, and Jyothi Noronha from The Influenza Research Database used in Influenza – Richard Scheuermann Bioinformatics Laboratory at an evolving problem! is an authentic research tool. It the University of Texas Southwestern Medical Centre is used to determine directions of influenza evolution at Dallas, USA for their help, feedback and support in and to identify new strains, as they emerge. The developing this activity. database is complex and so it is recommended that teachers work through the activity before giving it to The Influenza Research Database Bioinformatics students. The activity is structured and includes screen Resource Centre has been wholly funded with federal shots to make the database straightforward to use. funds from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, Each student will need to log in to the database Department of Health and Human Services, USA, and set up a workbench. Teachers may want to under Contract No. HHSN266200400041C. demonstrate this. World Health Organisation, Influenza (Seasonal), fact Influenza type A, segment 4, has been selected for this sheet number 211, April 2009 activity. This segment of RNA codes for the protein haemagglutinin, which is a surface protein used Evolution of influenza (influenza electronmicrograph) to identify influenza strains. After completing the by Dr F A Murphy, Centres for disease control activity, another phylogenetic tree may be generated and prevention, http://phil.cdc.gov/phil/details. using segment 6 which codes for neuraminidase. asp?pid=8432 Students answer questions as they work through the Images from the Influenza Research Database used database and produce a phylogenetic tree for selected with permission. strains of influenza. Their phylogenetic tree will reveal how genetically different the 2009 strains of influenza Designed and developed by the Centre for Learning were from earlier strains, due to antigenic shift, Technology, The University of Western Australia. and thus why so many people became sick. Immune Production team: Anton Ball, Pauline Charman, Jan memory is raised in the introduction to the activity. It Dook, Alwyn Evans, Dan Hutton, Bec McKinney, may be necessary to elaborate on this topic, focusing Emma Pointon, Paul Ricketts, Jodie Ween and Michael on immunisation and why it is recommended that Wheatley with thanks to Bob Fitzpatrick, Jenny Gull influenza vaccination is repeated each year. and Wendy Sanderson. SPICE resources and copyright Technical requirements All SPICE resources are available from the Centre for The teachers guide, background sheets, worksheet, Learning Technology at The University of Western and fact sheet require Adobe Reader (version 5 or Australia (“UWA”). Selected SPICE resources are later), which is a free download from get.adobe.com/ available through the websites of Australian State and reader/. Territory Education Authorities. The Influenza Research database requires a compatible Copyright of SPICE resources belongs to The University Javascript-enabled web browser. Minimum browser of Western Australia unless otherwise indicated. requirements are Internet Explorer 6.0, Netscape 8.0, Firefox 1.5 or Safari 1.2. Check with your IT support Teachers and students at Australian schools are person if Java is enabled. granted permission to reproduce, edit, recompile and include in derivative works the resources subject to conditions detailed at spice.wa.edu.au/usage. All questions involving copyright and use should be directed to SPICE at UWA. Web: spice.wa.edu.au Email: [email protected] Phone: (08) 6488 3917 Centre for Learning Technology (M016) The University of Western Australia 35 Stirling Highway Crawley WA 6009 ast1009 | Molecular evidence for evolution 4: Viral evolution (teachers guide) developed for the Department of Education WA © The University of Western Australia 2012 for conditions of use see spice.wa.edu.au/usage version 0.1 page 2 Licensed for NEALS Associated SPICE resources Molecular evidence for evolution 4: Viral evolution may be used in conjunction with related SPICE resources to teach the topic of molecular evidence for evolution. DESCRIPTION LEARNING PURPOSE Molecular evidence for evolution (overview) This learning pathway shows how a number of SPICE resources can be combined to teach the topic of molecular evidence for evolution. Molecular evidence for evolution 1: Classifying animals Engage Description to be added. Molecular evidence for evolution 2: Primates Explore Description to be added. Molecular evidence for evolution 3: Phylogenetic trees Explain Description to be added. Molecular evidence for evolution 4: Viral evolution Elaborate Students use bioinformatics tools within the Influenza Research Database to investigate how influenza viruses evolve. ast1009 | Molecular evidence for evolution 4: Viral evolution (teachers guide) developed for the Department of Education WA © The University of Western Australia 2012 for conditions of use see spice.wa.edu.au/usage version 0.1 page 3 Licensed for NEALS background sheet Influenza Influenza is a virus, that is, a pathogen (anything that Whether a virus is living is controversial. Viruses are causes disease). It causes respiratory tract infections unable to reproduce by themselves, even though they with symptoms including headache, sore-throat, body contain genetic material. In essence they are intracellular ache, high temperature, and cold-like symptoms such as parasites. Most living things only use DNA as genetic coughing and runny nose, that are usually quite mild. material, but some viruses contain DNA, others RNA. However there have been pandemics of influenza that Influenza viruses produce eleven different proteins that caused millions of deaths, eg the 1918 Spanish ‘flu (50 attach to molecules located on body cells, such as those million deaths); 1957 Asian ‘flu (1.5–2 million deaths); found in the human respiratory system, so they can enter and the 1968 Hong Kong ‘flu (1 million deaths). these cells and produce new viruses. Two of the eleven Influenza viruses can be transmitted by direct contact proteins are used to name the virus: haemagglutinin (H) with infected people, contact with contaminated and neuraminidase (N). There are 17 types of H and 10 objects, and inhalation of virus-laden aerosols. types of N and strains of influenza are named according Annually between 250 000 and 500 000 people die to the type of surface protein present. For example, of influenza around the world (data from the World H5N1 has H type 5 and N type 1 on its surface. Health Organisation). Influenza viruses contain eight strands or segments of Viruses are extremely small (between 20–300 nm). They RNA within a protein coat. These code for all proteins are able to enter host cells where they produce virions and enzymes that the virus requires to reproduce and (individual virus particles). Virions may then leave spread. RNA segment 4 codes for haemaggluttinin infected cells, travel to new cells, and infect them. while segment 6 codes for neuraminidase. neuraminidase (N) haemagglutinin (H) RNA influenza A virus ast1010 | Evidence for molecular evolution 4: Influenza (background sheet)
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