Characterization of a crucifer plant pre-rRNA processing complex.
In cruciferous plants, the primary pre-rRNA cleavage site (P site) is immediately downstream of four similar, highly conserved sequences (A(1), A(2), A(3) and B) located within the 5'-ETS (5'-external transcribed spacer). In the present study, we describe the characterization of a plant NF D (nuclear factor D) that binds and interacts specifically with this A(123)BP cluster in the rDNA sequence. NF D is a high-molecular-mass complex containing nucleolin, fibrillarin and U3 and U14 snoRNAs. Furthermore, we show that NF D binds and cleaves pre-rRNA specifically at the P site. Thus we conclude that NF D is a pre-rRNA processing complex that may first assemble on rDNA and then bind nascent pre-rRNA.
Sáez-Vasquez
J
J
LGDP UMR 5096, CNRS-IRD-Université de Perpignan, 52 Avenue Paul Alduy, 66860 Perpignan, France. saez@univ-perp.fr
Caparros-Ruiz
D
D
Barneche
F
F
Echeverría
M
M
D001937:Brassica / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism; D012322:RNA Precursors / Q000235:genetics* / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics* / Q000378:metabolism; D012335:RNA, Ribosomal / Q000235:genetics* / Q000378:metabolism
D009687:Nuclear Proteins; D012322:RNA Precursors; D018749:RNA, Plant; D012335:RNA, Ribosomal