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www.fludb.org Comparative Genomics in the Influenza Research Database 17 June 2011 Richard H. Scheuermann, Ph.D. Department of Pathology U.T. Southwestern Medical Center
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www.fludb.org NIAID-sponsored Bioinformatics Resource Centers
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www.fludb.org
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Query Results
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Workbench
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www.fludb.org Novel Data Features in IRD CEIRS Surveillance Data 3D Structures and Data Integration Sequence Feature Variant Types
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www.fludb.org CEIRS
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3D Structures & Integration Visualize protein structure in 3D Display sequence conservation heat map on the structure Highlight sequence features (epitopes, etc.) Download highlighted protein structure image
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SFVT approach VT-1I F D R L E T L I L VT-2I F N R L E T L I L VT-3I F D R L E T I V L VT-4L F D Q L E T L V S VT-5I F D R L E N L T L VT-6I F N R L E A L I L VT-7I Y D R L E T L I L VT-8I F D R L E T L V L VT-9I F D R L E N I V L VT-10I F E R L E T L I L VT-11 L F D Q M E T L V S Influenza A_NS1_nuclear-export-signal_137(10) Identify regions of protein/gene with known structural or functional properties – Sequence Features (SF) an alpha-helical region, the binding site for another protein, an enzyme active site, an immune epitope Determine the extent of sequence variation for each SF by defining each unique sequence as a Variant Type (VT) High-level, comprehensive grouping of all virus strains by VT membership for each SF independently Influenza A_NS1_alpha-helix_171(17)
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www.fludb.org Influenza A Sequence Features as of 10JUN2011 >4000 SFs total
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www.fludb.org VT for SF8 (nuclear export signal)
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www.fludb.org VT-1 strains
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www.fludb.org ADAPTIVE GENETIC DRIVERS OF SPECIES JUMP EVENTS
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www.fludb.org Flu pandemics of the 20 th and 21 st centuries initiated by species jump events 1918 flu pandemic (Spanish flu) – subtype H1N1 (avian origin) – estimated to have claimed between 2.5% to 5.0% of the world’s population (20 > 100 million deaths) Asian flu (1957 – 1958) – subtype H2N2 (avian origin) – 1 - 1.5 million deaths Hong Kong flu (1968 – 1969) – subtype H3N2 (avian origin) – between 750,000 and 1 million deaths 2009 H1N1 – subtype H1N1 (swine origin) – ~ 16,000 deaths as of March 2010
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www.fludb.org Pandemic stages Adaptive drivers
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www.fludb.org Basic reproductive number (R 0 ) Total number of secondary cases per case Reasonable surrogate of fitness Characteristics of pandemic viruses: – R 0 H >1, and – In genetic neighborhood of viruses with R 0 R>1 and R 0 H<1 Adaptive drivers Pandemic Viruses (R 0 H >1) Pandemic Viruses (R 0 H >1) Stuttering viruses (R 0 R>1 and R 0 H<1) Stuttering viruses (R 0 R>1 and R 0 H<1) Reservoir virus (R 0 R>1 and R 0 H<<1) Reservoir virus (R 0 R>1 and R 0 H<<1) A1A2
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www.fludb.org Adaptive drivers Pepin KM et al. (2010) “Identifying genetics markers of adaptation for surveillance of viral host jump” Nature Reviews Microbiology 8: 802-814.
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www.fludb.org Stuttering transmission and adaptive drivers Stuttering transmission can reveal adaptive drivers by evidence of convergent evolution – Odds of finding the same neutral mutation by chance in multiple species jumps is low – Therefore, finding same mutation in multiple independent species jump events is strong evidence for adaptive driver
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www.fludb.org Genetic convergence during species jump Virus isolate groups from IRD – Avian H5N1 (PB2) from Southeast Asia* up to 2003 (260 records) – reservoirs of source viruses – Human H5N1 (PB2) from Southeast Asia 2003-present (165 records) – many examples of independent species jumps Align amino acid sequence and calculate conservation score Identify highly conserved positions in avian records (≤1/260 variants) (557positions/759) – functionally restricted in reservoir Select subset in which two or more human isolates contained the same sequence variant – either due to human-human transmission or convergent evolution *China, Hong Kong, Indonesia, Thailand, Viet Nam
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www.fludb.org Strain Search – PB2 avian H5N1 Southeast Asia up to 2003
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www.fludb.org 260 PB2 records
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www.fludb.org Sequence variation analysis
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www.fludb.org Position order
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www.fludb.org Order by variation score
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www.fludb.org My Workbench
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www.fludb.org Convergent evolution candidates
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www.fludb.org E627K
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www.fludb.org E627K and species jump
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www.fludb.org K660R
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www.fludb.org Summary Human influenza pandemics are initiated by species jump events followed by sustained human to human transmission (R 0 H>1) Multiple independent occurrences of the same mutation during stuttering transmission is evidence of convergent evolution of adaptive drivers – hypotheses for experimental testing Surveillance for adaptive drivers in reservoir species could help anticipate the next pandemic N01AI40041
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www.fludb.org 41 Acknowledgments U.T. Southwestern – Richard Scheuermann – Burke Squires – Jyothi Noronha – Victoria Hunt – Shubhada Godbole – Brett Pickett – Ayman Al-Rawashdeh MSSM – Adolfo Garcia-Sastre – Eric Bortz – Gina Conenello – Peter Palese Vecna – Chris Larsen – Al Ramsey LANL – Catherine Macken – Mira Dimitrijevic U.C. Davis – Nicole Baumgarth Northrop Grumman – Ed Klem – Mike Atassi – Kevin Biersack – Jon Dietrich – Wenjie Hua – Wei Jen – Sanjeev Kumar – Xiaomei Li – Zaigang Liu – Jason Lucas – Michelle Lu – Bruce Quesenberry – Barbara Rotchford – Hongbo Su – Bryan Walters – Jianjun Wang – Sam Zaremba – Liwei Zhou IRD SWG – Gillian Air, OMRF – Carol Cardona, Univ. Minnesota – Adolfo Garcia-Sastre, Mt Sinai – Elodie Ghedin, Univ. Pittsburgh – Martha Nelson, Fogarty – Daniel Perez, Univ. Maryland – Gavin Smith, Duke Singapore – David Spiro, JCVI – Dave Stallknecht, Univ. Georgia – David Topham, Rochester – Richard Webby, St Jude USDA – David Suarez Sage Analytica – Robert Taylor – Lone Simonsen CEIRS Centers
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