|Telomeres in fungi. [PROOFS]|
Cohn M, Liti G, Barton DBH
Topics in Current Genetics (2006)
Category: telomere ¤ Added: Jan 30, 2006 ¤ Rating: ◊◊
Telomeres are the functional elements concluding and defining each linear chromosome in eukaryotes. They play an essential role in protecting genetic material and preventing genome loss during cell division. At the same time, and in stark contrast, they are remarkably dynamic regions: initial analyses of yeast genomes have shown, through comparative genomics, that regions close to telomeres are prone to rearrangements and duplication and thus are particularly variable between strains and species. This propensity for variation leads to the birth of new and alternative gene functions and helps to accelerate genome evolution and divergence. However, this special property, while making telomeric regions of even greater scientific interest, complicates investigation. Firstly, repetitive DNA is problematic to clone and sequence properly. Secondly, the reoccurring rearrangements and associated lack of synteny between the telomeric regions of even very closely related species creates daunting challenges for the comparative approach. This drives the development of special cloning and bioinformatic strategies. Such efforts should be fruitful, since a comparative approach of telomeres and subtelomeres promises many insights of significance to the research of ageing and cancer, chromosome dynamics in cell division, and the processes of evolution and speciation.