Studies with artificial extrachromosomal elements in trypanosomatids: could specificity in the initiation of DNA replication be linked to that in transcription?
Historically, artificial replicons have served as useful models for the definition of regulatory elements involved in chromosomal replication and transmission in yeast and DNA replication in bacteria. Here, Pradeep Patnaik examines what we have learnt so far from the replicative behaviour of various artificial extrachromosomal elements available for trypanosomatids. He highlights the involvement of transcription regulatory elements in virtually every eukaryotic origin of replication analysed in detail and, by drawing upon the extensive literature supporting a close association between DNA replication and transcription, he speculates that the nature and organization of origins of replication on a chromosome also may hold clues to the manner by which an organism regulates gene expression.
Patnaik
P K
PK
Division of Parasitology, National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK. ppatnai@nimr.mrc.ac.uk