TERRA in biology is an abbreviation for "TElomeric Repeat-containing RNA".[1] TERRA is RNA that is transcribed from telomeres — the repeating 6-nucleotide sequences that cap the ends of chromosomes. TERRA functions with shelterin to inhibit telomere lengthening by enzyme telomerase.[1] However, other studies have shown that under certain conditions TERRA can recruit telomerase to telomeres.[2]

TERRAs are essential for telomere length and maintenance.[3][2] At least four factors contribute to telomere maintenance: telomerase, shelterin, TERRA and the CST Complex.[4]

TERRA can also regulate telomere length by increasing euchromatin formation.[5] On the other hand, nonsense-mediated decay factor enrichment at telomeres may exist to prevent TERRA inhibition of telomerase.[1] TERRA levels vary during the cell cycle, decreasing during S phase, and increasing in the transition from G2 phase to G1 phase.[5]

References edit

  1. ^ a b c Luke B, Lingner J (2009). "TERRA: telomeric repeat-containing RNA". The EMBO Journal. 28 (17): 2503–2510. doi:10.1038/emboj.2009.166. PMC 2722245. PMID 19629047.
  2. ^ a b Zhu Y, Liu X, Geng X (2019). "Telomere and its role in the aging pathways: telomere shortening, cell senescence and mitochondria dysfunction". Biogerontology. 20 (1): 1–16. doi:10.1007/s10522-018-9769-1. PMID 30229407.
  3. ^ Montero JJ, López-Silanes I, Megías D, F Fraga M, Castells-García Á, Blasco MA (2018). "TERRA recruitment of polycomb to telomeres is essential for histone trymethylation marks at telomeric heterochromatin". Nature Communications. 9 (1): 1548. Bibcode:2018NatCo...9.1548M. doi:10.1038/s41467-018-03916-3. PMC 5906467. PMID 29670078.
  4. ^ Giraud-Panis MJ, Teixeira MT, Géli V, Gilson E (2010). "CST meets shelterin to keep telomeres in check". Molecular Cell. 39 (5): 665–676. doi:10.1016/j.molcel.2010.08.024. PMID 20832719.
  5. ^ a b Wang C, Zhao L, Lu S (2015). "Role of TERRA in the regulation of telomere length". International Journal of Biological Sciences. 11 (3): 316–323. doi:10.7150/ijbs.10528. PMC 4323371. PMID 25678850.