Organization of Telomeres During the Cell and Life Cycles of Trypanosoma brucei

摘要: The genome of Trypanosoma brucei contains about 120 chromosomes, which do not visibly condense during mitosis. We have analyzed the organization and segregation these chromosomes by in situ hybridization using fluorescent telomere probes. At onset mitosis, telomeres migrate from their nuclear peripheral location congregate into a central zone. This dense group then splits two entities that to opposite poles. Segregation continues until double-sized nucleus divides and, before cytokinesis occurs, reorganize discrete foci observed at interphase. During migration, are located free end mitotic spindle. Treatment with microtubule polymerization inhibitor rhizoxin prevents clustering chromosomal segregation. In insect-specific procyclic form as well non-dividing bloodstream stumpy form, tend cluster close periphery contrast, proliferative slender preferentially locate zone nucleus. Thus, closer those life cycle stages where telomeric expression sites for variant surface glycoprotein all inactive, suggesting transcriptional inactivation is related subnuclear localization.