Division and DNA synthesis in the kinetoplast ofCrithidia fasciculata.

In Critliidia fascicuJata division of the kinetoplast occurs prior to karyokinesis. Kinetoplast division involves the lateral replication of the nucleoid, and the subsequent constriction and 'pinching off' of the nucleoid and mitochondrial components. Two subunits are produced. DNA synthesis in the kinetoplast and the nucleus is overlapping but asynchronous. Experiments for short labelling times indicate that the kinetoplast S period either precedes, succeeds or is simultaneous with the nuclear period of DNA synthesis. The kinetoplast divides in a manner in which some radioactivity is transmitted to each unit.