Kinetoplazmák

Kinetoplazmák refer to the extranuclear DNA found in certain eukaryotic organisms, primarily within mitochondria and chloroplasts. These organelles are thought to have originated from endosymbiotic bacteria, and they retain their own circular DNA molecules, distinct from the nuclear genome. Mitochondrial DNA, or mtDNA, encodes essential components for cellular respiration, including subunits of the electron transport chain and ribosomal RNAs. Chloroplast DNA, or cpDNA, in plant cells and algae, contains genes vital for photosynthesis, such as those for the large subunit of RuBisCO and components of the photosystems. The genetic code within kinetoplasts can differ slightly from the standard nuclear genetic code, particularly in the interpretation of certain codons. Replication and gene expression of kinetoplast DNA occur independently of the nuclear cell cycle, although their activities are coordinated with the cell's overall metabolic needs. Studying kinetoplasts provides insights into organelle evolution, genetic variation, and the development of certain inherited diseases in humans, which can be caused by mutations in mtDNA.