UC Santa Cruz

The ability for RNA to adopt multiple structures from one sequence presents challenges when predicting RNA secondary structure. Most RNA in the cell is bound to protein, adding additional layers of complexity to the puzzle. Protein-RNA contacts are studied in this body of work within the context of telomerase, a ribonucleoprotein that adds telomeric DNA to the ends of chromosomes allowing cells preserve genomic integrity and prevent the DNA damage. Telomerase is composed of a protein and RNA component, each composed of multiple conserved domains. The contacts formed between these two units are important for understanding telomerase assembly and function. In the first study it is shown that a functionally critical domain within human telomerase RNA is structurally heterogeneous. This heterogeneity is eliminated with telomerase RNA is bound to the telomerase protein. The role of structural heterogeneity in a step-wise assembly pathway of telomerase is discussed. In the second study a previously characterized protein-RNA interaction in Tetrahymena thermophila is demonstrated to be due to a protein contaminant rather than a true telomerase protein-telomerase RNA interaction. This allows for the re-evaluation of previously proposed models for which protein-RNA interactions are important for telomerase function. Taken together these two studies shed light on the different protein-RNA interactions important for telomerase assembly and function.