Telomeres and Telomerase

Eukaryotic genomes are organized into linear chromosomes which require unique systems for protecting the ends. Telomeres are end-capping structures that prevent chromosome termini from undesirable fusion events. The integrity and length of telomeres are crucial for chromosome stability. Telomere integrity is maintained by telomeric proteins that specifically coat and protect telomeric DNA. The length of telomeric DNA is maintained by the telomerase enzyme that synthesizes telomeric DNA repeats onto chromosome ends from a short template sequence within its integral RNA component. Mutations that negatively affect telomerase, telomere integrity or length result in chromosome instability, cell death, and human disease.