Telomeres are nucleoprotein structures assembled at the end of eukaryotic chromosomes, protecting them from degradation and erroneous recombination events. For this reason, telomeres and telomerase, the enzyme that maintains telomere length homeostasis, are essential to genome integrity and are crucially implicated in tumorigenesis.
The long noncoding RNA TERRA (telomeric repeat-containing RNA) is transcribed at telomeres and represents a key component of telomere biology. Emerging evidence indicates that TERRA transcripts are critical regulators of telomere maintenance of cancer cells. Accordingly, TERRA molecules localize at chromosome ends and impaired localization of TERRA or altered TERRA expression associate with dysfunctional telomeres and genome instability. Nevertheless, little information is available on the dynamics of TERRA transcripts and the mechanisms of action of TERRA remain to be defined. Interestingly, TERRA associates with telomerase, but its role in the regulation of this enzyme in human cancer cells is still unknown.
Due to their central role in telomere biology, TERRA may represent novel cancer therapeutic targets.
We are interested in understanding the function and regulation of TERRA in human cancer cells. To this aim, we have developed a live-cell imaging assay to visualize and study endogenous TERRA transcripts expressed from a single telomere in living human cancer cells. By combining live-cell imaging with biochemical and molecular biology techniques we aim to define the dynamics of TERRA expression and localization at telomeres and characterize the role of TERRA in telomerase activity and telomere function in human cancer cells.
- Emilio Cusanelli, PI
- Nicole Bettin, Research Fellow
- Claudio Oss Pegorar, Research Fellow
- Irene Gialdini, Master Student
- Caterina Manzato, Trainee
- Angela Trinca, Bachelor Student
- Pascal Chartrand, University of Montreal, Canada
- Verena Jantsch, University of Vienna, Austria
- Michael J. Jantsch, Medical University of Vienna
Avogaro L, Oss Pegorar C, Bettin N, Cusanelli E. (2019) Generation of Cancer Cell Clones to Visualize Telomeric Repeat-containing RNA TERRA Expressed from a Single Telomere in Living Cells. J. Vis. Exp. (143), e58790.
Avogaro L, Querido E, Dalachi M, Jantsch M, Chartrand P, Cusanelli E. (2018) Live-cell imaging reveals the dynamics and function of single-telomere TERRA molecules in cancer cells. RNA Biology, 15(6): 787-796
Perez-Romero CA, Lalonde M, Chartrand P, Cusanelli E. (2018) Induction and relocalization of telomeric repeat-containing RNAs during diauxic shift in budding yeast. Current Genetics, 64(5):1117-1127.
Moradi-Fard S, Sarthi J, Tittel-Elmer M, Lalonde M, Cusanelli E, Chartrand P, Cobb J. (2016) Smc5/6 is a telomere-associated complex that regulates Sir4 binding and TPE. PLOS Genetics, 12(8): e1006268
Cusanelli E* and Chartrand P. (2015) Telomeric repeat-containing RNA TERRA: a noncoding RNA connecting telomere biology to genome integrity. Frontiers in Genetics, 6: 143. *Corresponding author
Cusanelli E and Chartrand P. (2014) Telomeric non-coding RNA TERRA in telomere biology. Wiley Interdiscip. Rev. RNA, 5(3): 407-419
Cusanelli E, Perez Romero CA, Chartrand P. (2013) Telomeric non-coding RNA TERRA is induced by telomere shortening to nucleate telomerase molecules at short telomeres. Molecular Cell, 51(6): 780-791
Gallardo F*, Laterreur N*, Cusanelli E, Ouenzar F, Querido E, Wellinger RJ, Chartrand P. (2011) Live cell imaging of telomerase RNA dynamics reveals cell cycle-dependent clustering of telomerase at elongating telomeres. Molecular Cell, 44(5): 819–827. * Equally contributed
Rita Levi Montalcini program, Italian Ministry of Education, University and Research (MIUR)