title: Conservation of a 29-base-pair sequence within maxicircle ARS fragments from six species of trypanosomes.
abstract: The maxicircles from Trypanosoma brucei, Herpetomonas samuelpessoai, Leptomonas seymouri, and Phytomonas davidi were examined for the presence of a 29-bp sequence termed CF29 that has been found in the ars 189 sequence from the Crithidia fasciculata maxicircle and in Lt-ars 189 from the maxicircle of Leishmania tarentolae. The CF29 sequence also contains a yeast consensus ARS of (T/A)TTTATPuTTT(T/A). All of the maxicircles examined contained specific fragments that hybridized to the CF29 probe. The non-replicating yeast plasmid vector YIp5 was used to clone these CF29-containing maxicircle fragments. High-frequency transformation was observed when these chimeric plasmids were used to transform Saccharomyces cerevisiae. Autonomous replication of these transforming plasmids was verified by Southern analysis of yeast-cell extracts using pBR322 as a hybridization probe. Therefore it appears that the CF29 sequence is widely conserved in kinetoplastid protozoa and is associated with ARS sequences in the maxicircles. Hybridization of the CF29 probe to a population of P. davidi minicircles was also observed. However, the YIp5 chimeric plasmid containing this CF29-hybridizing minicircle fragment failed to transform yeast.
mesh_terms: D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D002875:Chromosomes / Q000032:analysis*; D003421:Crithidia / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D009693:Nucleic Acid Hybridization; D012441:Saccharomyces cerevisiae / Q000235:genetics; D013045:Species Specificity; D014346:Trypanosoma brucei brucei / Q000235:genetics; D014351:Trypanosomatina / Q000235:genetics*