TRANSFER-RNA GENES TRANSCRIBED FROM THE PLASTID-LIKE DNA OF PLASMODIUM-FALCIPARUM

Besides their mitochondrial genome, malarial parasites contain a secon d organellar DNA, This 35 kb circular molecule has a number of feature s reminiscent of plastid DNAs. Sequence analysis shows that along with other genes the circle codes for 25 different tRNAs all of which are transcribed, Six of the tRNAs have some unusual features, and one has an intron, the only one found so far on the circle, Comparison of codo n and anticodon usage indicates that the 25 tRNAs are sufficient to de code all the protein genes present on the circle, The maintenance of s uch a parsimonious but complete translation system is further evidence for the functionality of the circle.