Kinetoplastid protozoa are the causative agents of visceral and cutaneous leishmaniasis, sleeping sickness and Chagas' disease in much of the tropical and subtropical world. These parasitic organisms are characterized by a unique form of mitochondrial DNA called a kineplast DNA or kDNA. This DNA consists of several thousand minicircles and about 25 maxicircles, all of which are interlocked into a single DNA network which is condensed into a highly organized disk-shaped structure at the base of the flagellum. Circular DNA molecules are released individually from the network, replicated and then rejoined to the network which eventually doubles in size as all circular DNA molecules become duplicated. The double sized network is then divided into two and a united size network is partitioned to each of two daughter cells prior to completion of cell division. This research will investigate the role of the group of histone-like kinetoplast proteins in the organization and segregation of the kDNA in the kinetoplastid Crithidia fasciculata.