RRC ID 4825
Author Barbezier N, Canino G, Rodor J, Jobet E, Saez-Vasquez J, Marchfelder A, Echeverría M.
Title Processing of a dicistronic tRNA-snoRNA precursor: combined analysis in vitro and in vivo reveals alternate pathways and coupling to assembly of snoRNP.
Journal Plant Physiol
Abstract The C/D box small nucleolar RNAs (snoRNAs) represent an essential class of small nucleolar RNAs that guide 2'-O-Rib methylation of ribosomal RNAs and other RNAs in eukaryotes. In Arabidopsis (Arabidopsis thaliana), >100 C/D snoRNAs have been identified, most of them encoded by polycistronic gene clusters, but little is known on the factors controlling their biogenesis. Here, we focus on the identification of factors controlling the processing of tRNA-snoRNA dicistronic precursors (pre-tsnoRNA) synthesized by RNA polymerase III and producing tRNA(Gly) and C/D snoR43. We produced radiolabeled RNA probes corresponding to different pre-tsnoRNA mutants to test their impact on processing in vitro by a recombinant tRNAse Z, the Arabidopsis endonuclease that processes the 3'end of tRNAs, and by nuclear extracts from cauliflower (Brassica oleracea) inflorescences that accurately process the pre-tsnoRNA. This was coupled to an in vivo analysis of the processing of tagged pre-tsnoRNA mutants expressed in Arabidopsis. Our results strongly implicate tRNase Z in endonucleolytic cleavage of the pre-tsnoRNA. In addition, they reveal an alternate pathway that could depend on a tRNA decay surveillance mechanism. Finally, we provide arguments showing that processing of pre-tsnoRNA, both in planta and by nuclear extracts, is coupled to the assembly of snoRNA with core proteins forming the functional snoRNP (for small nucleolar ribonucleoprotein complex).
Volume 150(3)
Pages 1598-610
Published 2009-7-1
DOI 10.1104/pp.109.137968
PII pp.109.137968
PMID 19420328
PMC PMC2705039
MeSH Arabidopsis / genetics* Arabidopsis / metabolism Base Sequence Models, Genetic Molecular Sequence Data Mutation Nucleic Acid Conformation RNA Polymerase III / metabolism RNA Precursors / genetics RNA Precursors / metabolism* RNA, Small Nucleolar / chemistry RNA, Small Nucleolar / genetics RNA, Small Nucleolar / metabolism* RNA, Transfer, Amino Acyl / metabolism* Recombinant Proteins / metabolism
IF 6.902
Times Cited 18
WOS Category PLANT SCIENCES
Resource
Arabidopsis / Cultured plant cells, genes pda09488