Article

Telomeric chromatin: replicating and wrapping up chromosome ends.

University of Geneva, Switzerland.
Current Opinion in Genetics & Development (impact factor: 8.09). 05/2001; 11(2):189-98. DOI:10.1016/S0959-437X(00)00178-7 pp.189-98
Source: PubMed

ABSTRACT Recent advances in our understanding of the specialized chromatin structure at telomeres, the ends of eukaryotic chromosomes, have focused on three separate areas: replication of telomeres through the coordinated action of conventional DNA polymerases and the telomerase enzyme, protection of the chromosome end from DNA damage checkpoint sensors and DNA-repair processes, and the discovery of a novel deacetylase enzyme (Sir2p) required for the establishment and maintenance of telomeric heterochromatin. Although the number of proteins and the complexity of their interactions at telomeres continues to grow, a picture of at least some of the major players and mechanisms underlying telomere replication, end 'capping' and chromatin assembly is beginning to emerge.

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Keywords

chromosome end
 
conventional DNA polymerases
 
coordinated action
 
DNA damage checkpoint sensors
 
DNA-repair processes
 
end 'capping'
 
interactions
 
major players
 
novel deacetylase enzyme
 
proteins
 
Recent advances
 
separate areas
 
specialized chromatin structure
 
telomeres