Evolution of plant telomerase RNAs: farther to the past, deeper to the roots

0554846 - BFÚ 2022 RIV GB eng J - Journal Article
Fajkus, Petr - Kilar, A. - Nelson, A. - Holá, Marcela - Peška, Vratislav - Goffová, I. - Fojtová, M. - Zachová, D. - Fulnečková, Jana - Fajkus, Jiří
Evolution of plant telomerase RNAs: farther to the past, deeper to the roots.
Nucleic Acids Research. Roč. 49, č. 13 (2021), s. 7680-7694. ISSN 0305-1048. E-ISSN 1362-4962
R&D Projects: GA ČR(CZ) GX20-01331X; GA MŠMT EF15_003/0000477
Institutional support: RVO:68081707 ; RVO:61389030
Keywords : template-boundary definition * secondary structure * polymerase-iii * snrna genes * sequence
OECD category: Biochemistry and molecular biology; Biochemistry and molecular biology (UEB-Q)
Impact factor: 19.160, year: 2021
Method of publishing: Open access
https://academic.oup.com/nar/article/49/13/7680/6310787

The enormous sequence heterogeneity of telomerase RNA (TR) subunits has thus far complicated their characterization in a wider phylogenetic range. Our recent finding that land plant TRs are, similarly to known ciliate TRs, transcribed by RNA polymerase III and under the control of the type-3 promoter, allowed us to design a novel strategy to characterize TRs in early diverging Viridiplantae taxa, as well as in ciliates and other Diaphoretickes lineages. Starting with the characterization of the upstream sequence element of the type 3 promoter that is conserved in a number of small nuclear RNAs, and the expected minimum TR template region as search features, we identified candidate TRs in selected Diaphoretickes genomes. Homologous TRs were then used to build covariance models to identify TRs in more distant species. Transcripts of the identified TRs were confirmed by transcriptomic data, RT-PCR and Northern hybridization. A templating role for one of our candidates was validated in Physcomitrium patens. Analysis of secondary structure demonstrated a deep conservation of motifs (pseudoknot and template boundary element) observed in all published TRs. These results elucidate the evolution of the earliest eukaryotic TRs. linking the common origin of TRs across Diaphoretickes, and underlying evolutionary transitions in telomere repeats.
Permanent Link: http://hdl.handle.net/11104/0329474