Secondary DNA structure analysis of the coding strand switch regions of five Leishmania major Friedlin chromosomes

As part of the EULEISH international genome project, a region of 74,674 nuc leotides from chromosome 21 of Leishmania major Friedlin was subcloned and sequenced; and 31 new coding sequences were predicted. Of particular intere st was a unique coding strand switching region covering 1.6 kb of DNA; and this was subjected to further investigation. Bioinformatic analysis of this region revealed an unusually high AT composition, a lack of putative hairp ins and a strong curvature of the DNA in agreement with the structural char acteristics of similar regions of other Leishmania chromosomes. These obser vations and a comparison with the secondary DNA structure of four other Lei shmania chromosomes and chromosomes of different organisms could suggest a functional role of this region in transcription and mitotic division.