Human telomerase and Cajal body ribonucleoproteins share a unique specificity of Sm protein association.
Cajal bodies are nuclear structures that host RNA modification and assembly reactions. Some RNAs transit Cajal bodies, while others must concentrate in Cajal bodies to function. Here we report that at least a subfraction of human telomerase RNA and individual resident Cajal body RNAs is associated with Sm proteins. Surprisingly, of seven Sm proteins assembled into a heteroheptameric ring, only a subset copurifies telomerase and Cajal body ribonucleoproteins. We show that a Cajal body RNA localization motif determines this specificity. These discoveries expand the cellular repertoire of Sm protein assemblies and their involvement in ribonucleoprotein localization and function.
Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, California 94720, USA.
Dragony
D
Fu
Kathleen
K
Collins
D000911:Antibodies, Monoclonal / Q000378:metabolism; D001324:Autoantigens; D002460:Cell Line; D002467:Cell Nucleus / Q000737:chemistry; D020541:Coiled Bodies / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D008956:Models, Chemical; D017433:Protein Structure, Secondary; D012313:RNA / Q000737:chemistry / Q000378:metabolism*; D020537:RNA, Small Nucleolar / Q000737:chemistry; D012261:Ribonucleoproteins / Q000378:metabolism*; D017411:Ribonucleoproteins, Small Nuclear / Q000737:chemistry / Q000378:metabolism*; D012680:Sensitivity and Specificity; D019098:Telomerase / Q000737:chemistry / Q000378:metabolism*; D055517:snRNP Core Proteins
D000911:Antibodies, Monoclonal; D001324:Autoantigens; D020537:RNA, Small Nucleolar; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D055517:snRNP Core Proteins; C422952:telomerase RNA; D012313:RNA; D019098:Telomerase