Extending the Applications of Telomere‐Anchored PCR for Telomere Length Measurements

Abstract

Chromosome ends contain repetitive, protein‐nucleotide sequences called telomeres that protect against DNA loss during replication. These noncoding sequences can vary in nucleotide identity as well as repeat sequence length. Our model system, Aspergillus nidulans, has a telomere sequence of 5’‐TTAGGG‐3’, which is the same as the human repeat sequence. Unlike in humans, who have a somewhat variable telomere length, those of A. nidulans are tightly regulated at roughly 110 bp. Using A. nidulans as a model, we previously designed an inexpensive and effective method termed telomere‐anchored PCR as an alternative for current telomere length methods that can be labor intensive and relatively expensive. However, the adaptability of this method and its efficiency at determining telomere length for organisms that might exhibit less stringent telomere length regulation remains uncharacterized. We initially examined the validity of this method in a similar species, Aspergillus oryzae. A. oryzae has a telomere repeat identity of 5’‐TTAGGGTCAACA‐3’ and has been shown to contain similar telomere lengths to A. nidulans of about 120 bp. Preliminary results suggest that telomere anchored PCR can function as an assay to determine telomere length in A. oryzae. This provides incentive to pursue optimization of the protocol for other Aspergillus species as well as additional organisms like Tetrahymena thermophila to further extend the applications of this quick and easy method.