title: Cajal body proteins differentially affect the processing of box C/D scaRNPs.
abstract: Small nuclear ribonucleoproteins (snRNPs), which are required for pre-mRNA splicing, contain extensively modified snRNA. Small Cajal body-specific ribonucleoproteins (scaRNPs) mediate these modifications. It is unknown how the box C/D class of scaRNPs localizes to Cajal Bodies (CBs). The processing of box C/D scaRNA is also unclear. Here, we explore the processing of box C/D scaRNA 2 and 9 by coilin. We also broaden our investigation to include WRAP53 and SMN, which accumulate in CBs, play a role in RNP biogenesis and associate with coilin. These studies demonstrate that the processing of an ectopically expressed scaRNA2 is altered upon the reduction of coilin, WRAP53 or SMN, but the extent and direction of this change varies depending on the protein reduced. We also show that box C/D scaRNP activity is reduced in a cell line derived from coilin knockout mice. Collectively, the findings presented here further implicate coilin as being a direct participant in the formation of box C/D scaRNPs, and demonstrate that WRAP53 and SMN may also play a role, but the activity of these proteins is divergent to coilin.
authors: Department of Biochemistry, The University of Mississippi Medical Center, Jackson, Mississippi 39216-4505, United States of America.
authors: Isioma I
authors: II
authors: Enwerem
authors: Department of Biochemistry and Biophysics, The University of Rochester Medical Center, Rochester, New York 14642, United States of America.
authors: Guowei
authors: G
authors: Wu
authors: Department of Biochemistry and Biophysics, The University of Rochester Medical Center, Rochester, New York 14642, United States of America.
authors: Yi Tao
authors: YT
authors: Yu
authors: Department of Biochemistry, The University of Mississippi Medical Center, Jackson, Mississippi 39216-4505, United States of America.
authors: Michael D
authors: MD
authors: Hebert
mesh_terms: D000818:Animals; D020541:Coiled Bodies / Q000235:genetics / Q000378:metabolism*; D017362:Cyclic AMP Response Element-Binding Protein / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D018832:Molecular Chaperones; D012322:RNA Precursors / Q000235:genetics; D012326:RNA Splicing / Q000235:genetics*; D012342:RNA, Small Nuclear / Q000096:biosynthesis* / Q000235:genetics; D017411:Ribonucleoproteins, Small Nuclear / Q000096:biosynthesis* / Q000235:genetics; D019098:Telomerase / Q000235:genetics
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D018832:Molecular Chaperones; D012322:RNA Precursors; D012342:RNA, Small Nuclear; D017411:Ribonucleoproteins, Small Nuclear; D019098:Telomerase; C535133:WRAP53 protein, human