U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Animal Parasitic Diseases Laboratory: Beltsville, MD
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    Resources
                        Our ScientistsSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Northeast Area Beltsville, Maryland (BARC) Beltsville Agricultural Research Center Animal Parasitic Diseases Laboratory Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            LORENZI, H - J Craig Venter Instituteitem
                                            KHAN, A - Washington University School Of Medicineitem
                                            BEHNKE, M - Washington University School Of Medicineitem
                                            LIU, L - University Of Georgiaitem
                                            NAMASIVAYAM, S - University Of Georgiaitem
                                            SESHADRI, S - Hospital For Sick Children (SICKKIDS)item
                                            HADJITHOMAS, M - J Craig Venter Instituteitem
                                            KARAMYCHEVA, S - J Craig Venter Instituteitem
                                            PINNEY, D - University Of Pennsylvaniaitem
                                            BRUNK, B - University Of Pennsylvaniaitem
                                            AJIOKA, J - Cambridge Institute Of Medical Researchitem
                                            AZJENBERG, D - Hospital And University Center Of Limogesitem
                                            BOOTHROYD, J - Stanford Universityitem
                                            BOYLE, J - University Of Pittsburghitem
                                            DARDE, M - Hospital And University Center Of Limogesitem
                                            Dubey, Jitenderitem
                                            GRIGG, M - National Instiute Of Allergy And Infectious Diseases (NIAID, NIH)item
                                            HOWE, D - University Of Kentuckyitem
                                            KIM, KAMI - Albert Einstein College Of Medicineitem
                                            Rosenthal, Benjaminitem
                                            SAEIJ, J - Massachusetts Institute Of Technologyitem
                                            SU, C - University Of Tennesseeitem
                                            WHITE, M - University Of San Franciscoitem
                                            ZHU, X - Chinese Academy Of Agricultural Sciencesitem
                                            PARKINSON, J - Hospital For Sick Children (SICKKIDS)item
                                            KISSINGER, J - University Of Georgiaitem
                                            ROOS, D - University Of Pennsylvaniaitem
                                            SIBLEY, L - Washington University School Of Medicine
  Submitted to: Nature Genetics
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 11/9/2015
                                    Publication  Date: 1/7/2016
                                    Citation: Lorenzi, H., Khan, A., Behnke, M.S., Liu, L., Namasivayam, S., Seshadri, S., Hadjithomas, M., Karamycheva, S., Pinney, D., Brunk, B., Ajioka, J., Azjenberg, D., Boothroyd, J.C., Boyle, J., Darde, M.L., Dubey, J.P., Grigg, M., Howe, D., Kim, K., Rosenthal, B.M., Saeij, J., Su, C.L., White, M., Zhu, X.Q., Parkinson, J., Kissinger, J.C., Roos, D.S., Sibley, L.D. 2016. Comparative genomic sequence variation of Toxoplasma gondii reveals local admixture drives concerted expansion and diversification of secreted pathogenesis determinants. Nature Genetics. 7:10147.Interpretive Summary: Toxoplasma gondii is among the most abundant parasites world-wide, infecting many wild and domestic animals and causing zoonotic infections in humans.  T. gondii differs substantially in its distribution from closely related parasites that typically have narrow, specialized host ranges.  We compared the genomes of 62 T. gondii isolates representative of global diversity to several closely related apicomplexan parasites.  Our findings reveal that the amplification and diversification of secretory pathogenesis determinants is the primary feature that distinguishes the closely related genomes of these biologically diverse parasites.  We further show that the unusual population structure of T. gondii is characterized by block inheritance of these tandemly clustered determinants, suggesting that they drive evolution of transmission, host range, and pathogencity.  This data will be of interest to microbiologists, parasitologists, and biologists interested in the genetics and genomics of infection and disease.
                                Technical Abstract: Toxoplasma gondii is among the most abundant parasites world-wide, infecting many wild and domestic animals and causing zoonotic infections in humans.  T. gondii differs substantially in its distribution from closely related parasites that typically have narrow, specialized host ranges. We undertook a comparative genomics approach to understand the diversity of the tissue-cyst forming coccidia focusing on T. gondii and its close relatives.  First, we generated additional genomic DNA sequence coverage (~25X coverage) and RNASeq data (>1,000 X mean coverage of coding seqeunce) to improve the assembly and annotation for the reference ME49 strain of T. gondii.  We also generated a whole genome sequence for H. hammondi (~65X coverage) and compared these two closely related parasites to the recently completed genomes for S. neurona 21 and N. caninum 22, which cause economically important diseases in horses and cattle, respectively.  Finally, to provide insight into genetic variation of T. gondii, we derived whole genome sequences for 62 isolates chosen to span present global diversity.  Among this set, 16 reference strains representing the major haplogroups were sequenced by both 454 (3 and 8 kb pair-end libraries) and Illumina (300 bp pair-end libraries) technologies and the resulting reads were assembled and annotated separately (~ 47X average sequence coverage).  The remaining strains were sequenced using Illumina only (average ~ 42X average sequence coverage) and were mapped to the reference strain ME49. We used this data to focus on three interpretive themes: 1) Comparison of T. gondii to its most closely related tissue-cyst forming coccidians; 2) Analysis of the core genome of T. gondii and how it has diversified; and 3) Examination of how the global population structure of T. gondii has been shaped by local admixture.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov