Poster number 42 submitted by Kaitlin Klotz
Structural and Functional Profiling of telomerase RNA domain deletion mutants in Trypanosoma brucei, a deep-branching parasitic agent of neuropathology in mammals
Kaitlin E. Klotz (Department of Biological Sciences-University of North Carolina at Charlotte), Abhishek Dey (Department of Biology-University of North Carolina at Chapel Hill), Arpita Saha (Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions-Cleveland State University), Bibo Li (Center for Gene Regulation in Health and Disease, Department of Biological, Geological, and Environmental Sciences, College of Sciences and Health Professions-Cleveland State University), Kausik Chakrabarti (Department of Biological Sciences-University of North Carolina at Charlotte)
The ribonucleoprotein (RNP) telomerase consists of a telomerase reverse transcriptase (TERT) protein to catalyze the addition of telomeric repeats to the ends of linear chromosomes and a telomerase RNA (TR) which provides the instructions for the addition of telomeric repeats. Recently, we demonstrated that the RNA component of active telomerase complex of the parasite Trypanosoma brucei, the causative agent of African sleeping sickness, adopts two different conformations in its two different life stages in mammals and insects, which might affect stage-specific parasite proliferation rate and telomerase. To better understand which domains of T. brucei RNA are necessary for proper folding of the RNA and telomerase activity, we have created eleven deletion mutants of T. brucei TR, determined the structural folds of six of these RNA mutants by in vivo RNA SHAPE analysis and performed telomerase activity assays to measure the effects of each domain deletion on the ability of telomerase to lengthen T. brucei telomeres. Here, we document how each domain is associated with the structure and function of telomerase and propose some ideas regarding how telomerase function may be modulated through induced mutations to telomerase RNA structural domains. Notably, deletion of an RNA helical structure, distal to the templating domain of the RNA for telomere synthesis and a unique C/D box snoRNA domain, significantly affects RNA biogenesis and activity of T. brucei telomerase. These results provide the first comprehensive nucleotide-resolution analysis of telomerase structure-function in an evolutionarily and clinically important parasitic protist.
Abhishek Dey, Anais Monroy-Eklund, Kaitlin Klotz, Arpita Saha, Justin Davis, Bibo Li, Alain Laederach, Kausik Chakrabarti, In vivo architecture of the telomerase RNA catalytic core in Trypanosoma brucei, Nucleic Acids Research, Volume 49, Issue 21, 2 December 2021, Pages 12445–12466, https://doi.org/10.1093/nar/gkab1042
Keywords: Telomerase RNA, Structure Dynamics, Trypanosoma brucei