TeloPCR-seq: a high-throughput sequencing approach for telomeres

We have developed a high-throughput sequencing approach that enables us to determine terminal telomere sequences from tens of thousands of individual Schizosaccharomyces pombe telomeres. This method provides unprecedented coverage of telomeric sequence complexity in fission yeast. S. pombe telomeres are composed of modular degenerate repeats that can be explained by variation in usage of the TER1 RNA template during reverse transcription. Taking advantage of this deep sequencing approach, we find that like' repeat modules are highly correlated within individual telomeres. Moreover, repeat module preference varies with telomere length, suggesting that existing repeats promote the incorporation of like repeats and/or that specific conformations of the telomerase holoenzyme efficiently and/or processively add repeats of like nature. After the loss of telomerase activity, this sequencing and analysis pipeline defines a population of telomeres with altered sequence content. This approach will be adaptable to study telomeric repeats in other organisms and also to interrogate repetitive sequences throughout the genome that are inaccessible to other sequencing methods.