University of Kentucky UKnowledge Veterinary Science Faculty Publications Veterinary Science 2-10-2015 Systems-Based Analysis of the Sarcocystis neurona Genome Identifies athwaP ys That Contribute to a Heteroxenous Life Cycle Tomasz Blazejewski Hospital for Sick Children, Canada Nirvana Nursimulu Hospital for Sick Children, Canada Viviana Pszenny National Institute of Allergy and Infectious Diseases, NIAID Sriveny Dangoudoubiyam University of Kentucky, [email protected] Sivaranjani Namasivayam University of Georgia Follow this and additional works at: https://uknowledge.uky.edu/gluck_facpub See next page for additional authors Part of the Veterinary Medicine Commons Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Repository Citation Blazejewski, Tomasz; Nursimulu, Nirvana; Pszenny, Viviana; Dangoudoubiyam, Sriveny; Namasivayam, Sivaranjani; Chiasson, Melissa A.; Chessman, Kyle; Tonkin, Michelle; Swapna, Lakshmipuram S.; Hung, Stacy S.; Bridgers, Joshua; Ricklefs, Stacy M.; Boulanger, Martin J.; Dubey, Jitender P.; Porcella, Stephen F.; Kissinger, Jessica C.; Howe, Daniel K.; Grigg, Michael E.; and Parkinson, John, "Systems-Based Analysis of the Sarcocystis neurona Genome Identifies athwaP ys That Contribute to a Heteroxenous Life Cycle" (2015). Veterinary Science Faculty Publications. 27. https://uknowledge.uky.edu/gluck_facpub/27 This Article is brought to you for free and open access by the Veterinary Science at UKnowledge. It has been accepted for inclusion in Veterinary Science Faculty Publications by an authorized administrator of UKnowledge. For more information, please contact [email protected]. Authors Tomasz Blazejewski, Nirvana Nursimulu, Viviana Pszenny, Sriveny Dangoudoubiyam, Sivaranjani Namasivayam, Melissa A. Chiasson, Kyle Chessman, Michelle Tonkin, Lakshmipuram S. Swapna, Stacy S. Hung, Joshua Bridgers, Stacy M. Ricklefs, Martin J. Boulanger, Jitender P. Dubey, Stephen F. Porcella, Jessica C. Kissinger, Daniel K. Howe, Michael E. Grigg, and John Parkinson Systems-Based Analysis of the Sarcocystis neurona Genome Identifies athwaP ys That Contribute to a Heteroxenous Life Cycle Notes/Citation Information Published in mBio, v. 6, issue. 1, e02445-14, p. 1-16. Copyright © 2015 Blazejewski et al. This is an open-access article distributed under the terms of the Creative Commons Attribution- Noncommercial-ShareAlike 3.0 Unported license, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original author and source are credited. Digital Object Identifier (DOI) http://dx.doi.org/10.1128/mBio.02445-14 This article is available at UKnowledge: https://uknowledge.uky.edu/gluck_facpub/27 RESEARCH ARTICLE crossmark Systems-Based Analysis of the Sarcocystis neurona Genome Identifies Pathways That Contribute to a Heteroxenous Life Cycle Tomasz Blazejewski,a Nirvana Nursimulu,a,b Viviana Pszenny,c Sriveny Dangoudoubiyam,d Sivaranjani Namasivayam,e Melissa A. Chiasson,c Kyle Chessman,a,b Michelle Tonkin,f Lakshmipuram S. Swapna,a Stacy S. Hung,a,g Joshua Bridgers,e Stacy M. Ricklefs,h Martin J. Boulanger,f Jitender P. Dubey,h Stephen F. Porcella,i Jessica C. Kissinger,e,j,k Daniel K. Howe,d Michael E. Grigg,c John Parkinsona,g,l Program in Molecular Structure and Function, Hospital for Sick Children, Toronto, Ontario, Canadaa; Department of Computer Science, University of Toronto, Toronto, Ontario, Canadab; Molecular Parasitology Section, Laboratory of Parasitic Diseases, NIAID, National Institutes of Health, Bethesda, Maryland, USAc; Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, Kentucky, USAd; Department of Genetics, University of Georgia, Athens, Georgia, USAe; Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canadaf; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canadag; U.S. Department of Agriculture, Animal Parasitic Diseases Laboratory, Beltsville Agricultural Research Center, Agricultural Research Service, Beltsville, Maryland, USAh; Genomics Unit, Research Technologies Section, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, USAi; Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USAj; Institute of Bioinformatics, University of Georgia, Athens, Georgia, USAk; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canadal ABSTRACT Sarcocystis neurona is a member of the coccidia, a clade of single-celled parasites of medical and veterinary impor- tance including Eimeria, Sarcocystis, Neospora, and Toxoplasma. Unlike Eimeria, a single-host enteric pathogen, Sarcocystis, Neospora, and Toxoplasma are two-host parasites that infect and produce infectious tissue cysts in a wide range of intermediate hosts. As a genus, Sarcocystis is one of the most successful protozoan parasites; all vertebrates, including birds, reptiles, fish, and mammals are hosts to at least one Sarcocystis species. Here we sequenced Sarcocystis neurona, the causal agent of fatal equine protozoal myeloencephalitis. The S. neurona genome is 127 Mbp, more than twice the size of other sequenced coccidian ge- nomes. Comparative analyses identified conservation of the invasion machinery among the coccidia. However, many dense- granule and rhoptry kinase genes, responsible for altering host effector pathways in Toxoplasma and Neospora, are absent from S. neurona. Further, S. neurona has a divergent repertoire of SRS proteins, previously implicated in tissue cyst formation in Toxoplasma. Systems-based analyses identified a series of metabolic innovations, including the ability to exploit alternative sources of energy. Finally, we present an S. neurona model detailing conserved molecular innovations that promote the transi- tion from a purely enteric lifestyle (Eimeria) to a heteroxenous parasite capable of infecting a wide range of intermediate hosts. IMPORTANCE Sarcocystis neurona is a member of the coccidia, a clade of single-celled apicomplexan parasites responsible for major economic and health care burdens worldwide. A cousin of Plasmodium, Cryptosporidium, Theileria, and Eimeria, Sarco- cystis is one of the most successful parasite genera; it is capable of infecting all vertebrates (fish, reptiles, birds, and mammals— including humans). The past decade has witnessed an increasing number of human outbreaks of clinical significance associated with acute sarcocystosis. Among Sarcocystis species, S. neurona has a wide host range and causes fatal encephalitis in horses, marine mammals, and several other mammals. To provide insights into the transition from a purely enteric parasite (e.g., Eime- ria) to one that forms tissue cysts (Toxoplasma), we present the first genome sequence of S. neurona. Comparisons with other coccidian genomes highlight the molecular innovations that drive its distinct life cycle strategies. Received 7 December 2014 Accepted 12 December 2014 Published 10 February 2015 Citation Blazejewski T, Nursimulu N, Pszenny V, Dangoudoubiyam S, Namasivayam S, Chiasson MA, Chessman, Tonkin M, Swapna LS, Hung SS, Bridgers J, Ricklefs SM, Boulanger MJ, Dubey JP, Porcella SF, Kissinger JC, Howe DK, Grigg ME, Parkinson J. 2015. Systems-based analysis of the Sarcocystis neurona genome identifies pathways that contribute to a heteroxenous life cycle. mBio 6(1):e02445-14. doi:10.1128/mBio.02445-14. Editor Louis M. Weiss, Albert Einstein College of Medicine Copyright © 2015 Blazejewski et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-ShareAlike 3.0 Unported license, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original author and source are credited. Address correspondence to John Parkinson, [email protected], or Michael E. Grigg, [email protected]. This article is a direct contribution from a Fellow of the American Academy of Microbiology. he coccidia are a large clade of protozoan parasites within the cysts surrounded by glycosylated cyst walls. Different species and Tphylum Apicomplexa. In addition to a single definitive host even strains exhibit distinct patterns of organ tropism, with species in which the parasite undergoes its sexual cycle, a subgroup Toxoplasma forming cysts in any organ, whereas Sarcocystis cysts of coccidia, the members of the family Sarcocystidae (Sarcocystis, are largely restricted to muscle. Ingestion of tissue cysts through Toxoplasma, and Neospora) have evolved the ability to infect a predation or scavenging by the definitive host propagates the life broad range of intermediate hosts (1, 2). To drive this transition, cycle (e.g., felids for Toxoplasma, canids for Neospora, and hu- the members of the family Sarcocystidae produce infectious tissue mans for two Sarcocystis species) (3). January/February 2015 Volume 6 Issue 1 e02445-14 ® mbio.asm.org 1 Blazejewski et al. To survive and persist in their respective hosts, apicomplexan TABLE 1 Genome statistics parasites have evolved a variety of molecular strategies. These in- Parameter Statistic clude a group of specialized proteins that facilitate parasite entry, Genome size (bp) 130,222,184 egress, and colonization, as well as molecular decoys that modu- Genome GC% 51.5 late host immune signaling (4, 5). The majority of these proteins No. of scaffolds 116 localize to exocytic organelles (micronemes,