title: Identification of a new RNA.RNA interaction site for human telomerase RNA (hTR): structural implications for hTR accumulation and a dyskeratosis congenita point mutation.
abstract: The enzyme telomerase is a ribonucleoprotein that has a critical role in the maintenance of stable telomeres in organisms that possess linear chromosomes. Using a recently developed single molecule fluorescence coincidence method, we have studied the RNA component of telomerase (hTR) and directly observed multimerisation of hTR in solution. RNA mutagenesis and blocking oligonucleotides were employed to identify the single-stranded internal loop J7b/8a as an important and specific hTR.hTR interaction site. This observation was confirmed by studies on a model RNA fragment (hTR(380-444)), comprising part of the H/ACA domain, the internal loop J7b/8a and the CR7 domain, that was found to dimerise. Substitution mutagenesis within the proposed RNA.RNA interaction site of hTR(380-444) resulted in a loss of dimerisation potential and insertion of the dyskeratosis congenita mutation C408G led to a significant reduction in dimer formation. Together, these results suggest that this RNA.RNA interaction site may be functionally relevant.
authors: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors: Xiaojun
authors: X
authors: Ren
authors: Gérald
authors: G
authors: Gavory
authors: Haitao
authors: H
authors: Li
authors: Liming
authors: L
authors: Ying
authors: David
authors: D
authors: Klenerman
authors: Shankar
authors: S
authors: Balasubramanian
mesh_terms: D001665:Binding Sites / Q000235:genetics; D019281:Dimerization; D019871:Dyskeratosis Congenita / Q000201:enzymology / Q000235:genetics; D004587:Electrophoresis, Agar Gel; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D017354:Point Mutation; D012313:RNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013050:Spectrometry, Fluorescence / Q000379:methods; D019098:Telomerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D012313:RNA; D019098:Telomerase