Publication details
Evolution of plant telomerase RNAs: farther to the past, deeper to the roots
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| Year of publication | 2022 |
| Type | Appeared in Conference without Proceedings |
| Citation | |
| Description | Telomerase, a specific ribonucleoprotein enzyme complex, solves the shortening of linear chromosomes by adding short telomeric sequences, using a catalytic activity of its Telomerase Reverse Transcriptase subunit while guided by Telomerase RNA (TR), which serves as a template for telomeres elongation. The end replication problem and emergence of telomerase are often associated with the earliest steps of eukaryotic evolution. Characterisation of TR was challenging yet possible, thanks to the utilisation of conservation of the mode of TR transcription by RNA Polymerase III (RNAP III) and structural domains known to be essential for TR function. By applying advanced bioinformatics tools, especially covariance models and methods for massive data handling, we could take advantage of the type 3 RNAP III promoter sequence conservation to identify TR candidate genes across a wide range of early–diverging eukaryotes. We validated in silico research at several levels: the presence of TR transcripts was examined in RNAseq data, moreover selected TR transcripts were demonstrated using wet-lab approaches, such as Northern hybridisation and RT-PCR. Additionally, we performed TR functional testing by using knock-out mutant, which showed telomere shortening and the loss of telomerase activity in a model plant Physcomitrium patens. With our research, we were able to identify TR across the Viridiplantae and discover novel TRs in neighbouring branches of Diaphoretickes mega-group- Ciliates and Stramenopiles, which provided substantial knowledge on the early steps of TR evolution. |