Plasmodium falciparum unexpectedly has two organelle-like genomes. One has characteristics reminiscent of chloroplast DNAs while the other appears to be a highly unusual mitochondrial genome. The putative mitochondrial genome is very small and encodes small regions with homology to ribosomal RNA in a discontinuous and scrambled manner. Conserved core regions are retained but variable regions are largely absent. The characteristics of the rRNA fragments suggest that they may be functional in ribosomes. This proposal is designed to determine if the fragments are in fact in ribosomes and to assess some of the characteristics of those ribosomes. The discontinuous rRNA fragments will be mapped and compared to other rRNAs, looking for conserved structure-function correlations. The presence of the discontinuous fragments in particles will be evaluated and the general characteristics of such particles determined. The subcellular location of the putative mitochondrial genome will be evaluated and investigations of ribosome function will be initiated. %%% The unusual nature of the discontinuous rRNAs suggests that understanding their role in ribosomes will increase understanding of fundamental ribosomal functions.
