Structural and functional characterization of human telomerase RNA processing and cajal body localization signals.
The RNA component of human telomerase (hTR) includes H/ACA and CR7 domains required for 3' end processing, localization, and accumulation. The terminal loop of the CR7 domain contains the CAB box (ugAG) required for targeting of scaRNAs to Cajal bodies (CB) and an uncharacterized sequence required for accumulation and processing. To dissect out the contributions of the CR7 stem loop to hTR processing and localization, we solved the solution structures of the 3' terminal stem loops of hTR CR7 and U64 H/ACA snoRNA, and the 5' terminal stem loop of U85 C/D-H/ACA scaRNA. These structures, together with analysis of localization, processing, and accumulation of hTRs containing nucleotide substitutions in the CR7 domain, identified the sequence and structural requirements of the hTR processing and CB localization signals and showed that these signals are functionally independent. Further, 3' end processing was found to be a prerequisite for translocation of hTR to CBs.
Theimer
Carla A
CA
Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095-1569, USA.
Jády
Beáta E
BE
Chim
Nicholas
N
Richard
Patricia
P
Breece
Katherine E
KE
Kiss
Tamás
T
Feigon
Juli
J
D020029:Base Pairing; D001483:Base Sequence; D020541:Coiled Bodies / Q000378:metabolism*; D003545:Cysteine / Q000235:genetics; D019871:Dyskeratosis Congenita / Q000235:genetics; D005998:Glycine / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009711:Nucleotides / Q000737:chemistry; D012313:RNA / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D026721:RNA 3' End Processing; D034443:RNA Transport; D020537:RNA, Small Nucleolar / Q000737:chemistry; D012996:Solutions; D019098:Telomerase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D009711:Nucleotides; D020537:RNA, Small Nucleolar; D012996:Solutions; C422952:telomerase RNA; D012313:RNA; D019098:Telomerase; D003545:Cysteine; D005998:Glycine