title: Malarial parasite diversity in chimpanzees: the value of comparative approaches to ascertain the evolution of Plasmodium falciparum antigens.
abstract: BACKGROUND
  Plasmodium falciparum shares its most recent common ancestor with parasites found in African apes; these species constitute the so-called Laverania clade. In this investigation, the evolutionary history of Plasmodium lineages found in chimpanzees (Pan troglodytes) was explored.
  
  
  METHODS
  Here, the remainders of 74 blood samples collected as part of the chimpanzees' routine health examinations were studied. For all positive samples with parasite lineages belonging to the Laverania clade, the complete mitochondrial genome (mtDNA), the gene encoding dihydrofolate reductase-thymidylate synthase (dhfr-ts), the chloroquine resistance transporter (Pfcrt), the circumsporozoite protein (csp), merozoite surface protein 2 (msp2), and the DBL-1 domain from var2CSA were amplified, cloned, and sequenced. Other Plasmodium species were included in the mtDNA, dhfr-ts, and csp analyses. Phylogenetic and evolutionary genetic analyses were performed, including molecular clock analyses on the mtDNA.
  
  
  CONCLUSIONS
  Nine chimpanzees were malaria positive (12.2%); four of those infections were identified as P. falciparum, two as a Plasmodium reichenowi-like parasite or Plasmodium sp., one as Plasmodium gaboni, and two as Plasmodium malariae. All P. falciparum isolates were resistant to chloroquine indicating that the chimpanzees acquired such infections from humans in recent times. Such findings, however, are not sufficient for implicating chimpanzees as an animal reservoir for P. falciparum.Timing estimates support that the Laverania clade has co-existed with hominids for a long-period of time. The proposed species P. gaboni, Plasmodium billbrayi, and Plasmodium billcollinsi are monophyletic groups supporting that they are indeed different species.An expanded CSP phylogeny is presented, including all the Laverania species and other malarial parasites. Contrasting with other Plasmodium, the Laverania csp exhibits great conservation at the central tandem repeat region. Msp2 and var2CSA, however, show extended recent polymorphism in P. falciparum that likely originated after the P. reichenowi-P. falciparum split. The accumulation of such diversity may indicate adaptation to the human host. These examples support the notion that comparative approaches among P. falciparum and its related species will be of great value in understanding the evolution of proteins that are important in parasite invasion of the human red blood cell, as well as those involved in malaria pathogenesis.
authors.affiliation: Center for Evolutionary Medicine and Informatics, The Biodesign Institute, Arizona State University, Tempe, Arizona, USA. Ananias.Escalante@asu.edu.
authors.forename: M Andreína
authors.initials: MA
authors.lastname: Pacheco
authors.forename: Michael
authors.initials: M
authors.lastname: Cranfield
authors.forename: Kenneth
authors.initials: K
authors.lastname: Cameron
authors.forename: Ananias A
authors.initials: AA
authors.lastname: Escalante
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D019143:Evolution, Molecular; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008288:Malaria / Q000469:parasitology / Q000662:veterinary*; D008297:Male; D008969:Molecular Sequence Data; D002679:Pan troglodytes; D010802:Phylogeny; D010961:Plasmodium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D018419:Primate Diseases / Q000469:parasitology*; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial; D016054:DNA, Protozoan
references.citation: BMC Evol Biol. 2012 Nov 14;12:219
references.pmid: 23151308
references.citation: Proc Natl Acad Sci U S A. 2005 Feb 8;102(6):1980-5
references.pmid: 15684081
references.citation: Mol Biol Evol. 1986 Sep;3(5):418-26
references.pmid: 3444411
references.citation: Proc Natl Acad Sci U S A. 1998 Jul 7;95(14):8124-9
references.pmid: 9653151
references.citation: Nature. 2010 Feb 4;463(7281):653-6
references.pmid: 20090678
references.citation: Mol Biochem Parasitol. 1998 Apr 1;92(1):187-92
references.pmid: 9574922
references.citation: PLoS Pathog. 2010 Feb 12;6(2):e1000765
references.pmid: 20169187
references.citation: J Biol Chem. 2004 May 21;279(21):21824-32
references.pmid: 15007056
references.citation: J Mol Evol. 1985;22(2):160-74
references.pmid: 3934395
references.citation: Infect Genet Evol. 2011 Jan;11(1):209-21
references.pmid: 20849978
references.citation: Lancet. 2004 Mar 27;363(9414):1017-24
references.pmid: 15051281
references.citation: Mol Biochem Parasitol. 2002 Nov-Dec;125(1-2):83-90
references.pmid: 12467976
references.citation: Nature. 2010 Sep 23;467(7314):420-5
references.pmid: 20864995
references.citation: PLoS Comput Biol. 2010 Sep 16;6(9):
references.pmid: 20862303
references.citation: Mol Biol Evol. 2008 Oct;25(10):2233-9
references.pmid: 18687771
references.citation: Nat Med. 2004 Apr;10(4):406-10
references.pmid: 15034567
references.citation: Infect Immun. 2012 Dec;80(12):4177-85
references.pmid: 22966050
references.citation: Genetics. 1998 May;149(1):189-202
references.pmid: 9584096
references.citation: Trends Parasitol. 2011 May;27(5):222-9
references.pmid: 21354860
references.citation: J Exp Med. 2005 Jan 3;201(1):27-33
references.pmid: 15630135
references.citation: Mol Biochem Parasitol. 2001 Apr 25;114(1):125-7
references.pmid: 11356522
references.citation: Mol Biol Evol. 2007 Jan;24(1):26-53
references.pmid: 17047029
references.citation: PLoS Pathog. 2011 Apr;7(4):e1002015
references.pmid: 21490952
references.citation: Cell. 1987 Jan 30;48(2):311-9
references.pmid: 3802196
references.citation: Syst Biol. 2005 Oct;54(5):719-30
references.pmid: 16243759
references.citation: Proc Natl Acad Sci U S A. 2005 Sep 6;102(36):12819-24
references.pmid: 16126901
references.citation: Lancet. 2001 Sep 15;358(9285):890-1
references.pmid: 11567708
references.citation: PLoS Biol. 2006 May;4(5):e88
references.pmid: 16683862
references.citation: Hereditas. 2000;133(3):217-28
references.pmid: 11433966
references.citation: Nat Methods. 2011 Sep 29;8(10):785-6
references.pmid: 21959131
references.citation: Proc Natl Acad Sci U S A. 2009 Sep 1;106(35):14902-7
references.pmid: 19666593
references.citation: Mol Biol Evol. 2005 Aug;22(8):1686-93
references.pmid: 15858201
references.citation: Mol Biol Evol. 2010 Sep;27(9):2198-209
references.pmid: 20427419
references.citation: Science. 1996 Jun 7;272(5267):1502-4
references.pmid: 8633247
references.citation: Mol Cell Biol. 1991 Feb;11(2):963-71
references.pmid: 1990294
references.citation: Science. 2003 Apr 11;300(5617):318-21
references.pmid: 12690197
references.citation: Proc Natl Acad Sci U S A. 1996 Oct 15;93(21):11889-94
references.pmid: 8876233
references.citation: Malar J. 2013 Mar 27;12:113
references.pmid: 23537145
references.citation: Am J Trop Med Hyg. 1958 Jan;7(1):20-4
references.pmid: 13508992
references.citation: J Parasitol. 2013 Aug;99(4):662-8
references.pmid: 23517409
references.citation: Trends Parasitol. 2011 Jun;27(6):231-2
references.pmid: 21497136
references.citation: EMBO Rep. 2005 Aug;6(8):775-81
references.pmid: 16025132
references.citation: Exp Parasitol. 1994 Sep;79(2):106-16
references.pmid: 7914494
references.citation: PLoS Med. 2011 Dec;8(12):e1001142
references.pmid: 22205883
references.citation: Mol Biol Evol. 2011 Oct;28(10):2731-9
references.pmid: 21546353
references.citation: Proc Natl Acad Sci U S A. 2013 Apr 23;110(17):7020-5
references.pmid: 23569255
references.citation: Syst Biol. 2003 Oct;52(5):696-704
references.pmid: 14530136
references.citation: Mol Biol Evol. 1992 May;9(3):381-93
references.pmid: 1584009
references.citation: J Parasitol. 2005 Jun;91(3):683-5
references.pmid: 16108566
references.citation: Mol Biol Evol. 1995 Jul;12(4):616-26
references.pmid: 7659017
references.citation: Proc Natl Acad Sci U S A. 1994 Nov 22;91(24):11373-7
references.pmid: 7972067
references.citation: Syst Biol. 2007 Dec;56(6):879-86
references.pmid: 18027281
references.citation: Emerg Infect Dis. 2010 Dec;16(12):1956-9
references.pmid: 21122230
references.citation: Bioinformatics. 2003 Aug 12;19(12):1572-4
references.pmid: 12912839
references.citation: Mol Microbiol. 2005 May;56(3):774-88
references.pmid: 15819631
references.citation: Proc Natl Acad Sci U S A. 2012 May 15;109(20):7817-22
references.pmid: 22547819
references.citation: Infect Genet Evol. 2010 Mar;10(2):298-303
references.pmid: 20097310
references.citation: J Infect Dis. 2010 May 15;201(10):1544-50
references.pmid: 20380562
references.citation: Proc Natl Acad Sci U S A. 2000 Jun 20;97(13):6994-7001
references.pmid: 10860962
references.citation: J Exp Med. 2011 Feb 14;208(2):341-56
references.pmid: 21262960
references.citation: Nat Genet. 2007 Jan;39(1):120-5
references.pmid: 17159978
references.citation: PLoS Pathog. 2011 Feb;7(2):e1001283
references.pmid: 21383971
references.citation: Adv Parasitol. 2013;81:203-22
references.pmid: 23384624
references.citation: PLoS Pathog. 2009 May;5(5):e1000446
references.pmid: 19478877
references.citation: J Infect Dis. 2002 Mar 15;185(6):820-7
references.pmid: 11920300
references.citation: Exp Parasitol. 2007 Jan;115(1):32-40
references.pmid: 16797008
references.citation: PLoS One. 2008 May 28;3(5):e2281
references.pmid: 18509456
references.citation: BMC Evol Biol. 2011 Oct 12;11:299
references.pmid: 21992100
references.citation: PLoS One. 2012;7(4):e34990
references.pmid: 22536346
references.citation: Proc Natl Acad Sci U S A. 2010 Jun 8;107(23):10561-6
references.pmid: 20498054
references.citation: Mol Biochem Parasitol. 2007 Oct;155(2):103-12
references.pmid: 17669514
references.citation: J Biol Chem. 2003 Oct 17;278(42):40905-10
references.pmid: 12904297
references.citation: J Biol Chem. 2005 May 27;280(21):20524-9
references.pmid: 15781464