title: First complete chromosomal organization of a protozoan plant parasite (Phytomonas spp.).
abstract: Phytomonas spp. are members of the family Trypanosomatidae that parasitize plants and may cause lethal diseases in crops such as Coffee Phloem necrosis, Hartrot in coconut, and Marchitez sorpresiva in oil palm. In this study, the molecular karyotype of 6 isolates from latex plants has been entirely elucidated by pulsed-field gel electrophoresis and DNA hybridization. Twenty-one chromosomal linkage groups constituting heterologous chromosomes and sizing between 0.3 and 3 Mb could be physically defined by the use of 75 DNA markers (sequence-tagged sites and genes). From these data, the genome size can be estimated at 25.5 (+/-2) Mb. The physical linkage groups were consistently conserved in all strains examined. Moreover, the finding of several pairs of different-sized homologous chromosomes strongly suggest diploidy for this organism. The definition of the complete molecular karyotype of Phytomonas represents an essential primary step toward sequencing the genome of this parasite of economical importance.
authors.affiliation: CIRAD, Department Biological Systems, Research Unit 29 Etiology of Wilts, TA A-29/F, 34398 Montpellier Cedex 5, Montpellier, France.
authors.forename: Clotilde
authors.initials: C
authors.lastname: Marín
authors.forename: Blandine
authors.initials: B
authors.lastname: Alberge
authors.forename: Michel
authors.initials: M
authors.lastname: Dollet
authors.forename: Michel
authors.initials: M
authors.lastname: Pagès
authors.forename: Patrick
authors.initials: P
authors.lastname: Bastien
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D040503:Coffea / Q000469:parasitology; D004171:Diploidy; D018503:Genome, Protozoan / Q000235:genetics*; D009336:Necrosis / Q000235:genetics; D052585:Phloem / Q000469:parasitology; D010935:Plant Diseases / Q000235:genetics / Q000469:parasitology; D014351:Trypanosomatina / Q000235:genetics*