Lake Forest College, Biology, Lake Forest, IL 60045
Eukaryotic chromosome ends possess repetitive sequences and binding proteins known as telomeres, which protect the chromosomes from degradation. Telomeres are maintained by telomerase, an enzyme that includes both a protein and an RNA component. Between species, the telomerase protein is highly conserved, whereas the telomerase RNA can vary substantially in sequence and secondary structure. The filamentous fungi Aspergillus nidulans maintains a 6-nucleotide telomere repeat sequence, making the search for the telomerase RNA in the recently completed genome sequence nearly impossible. To identify the RNA sequence in A. nidulans, we are using a comparative genomic approach with a related organism, Aspergillus oryzae. This species contains an unusual 12bp telomeric repeat sequence, increasing the chance of finding the telomerase RNA. Recently, 13 possible sequences in the genome were identified in silico, and we are in process of running RT-PCR to determine if these locations are indeed transcribed into RNA.
[Abstract (DOC)]