Evidence for involvement of NFBP in processing of ribosomal RNA.
J Cell Physiol
; 214(2): 381-8, 2008 Feb.
Article
en En
| MEDLINE
| ID: mdl-17654514
ABSTRACT
Ribosomal RNA (rRNA) in vertebrates is initially transcribed as a single 47S precursor which is modified by the addition of 2'-O-methyl ribose moieties, pseudouridines, and methyl groups, followed by cleavage at several sites to produce the mature 28S, 18S, and 5.8S rRNAs. Cleavage of the rRNA precursor to generate the 18S rRNA is mediated by a ribonucleoprotein (RNP) complex termed the processome containing U3, a box C/D small nucleolar RNA (snoRNA), and at least 28 cellular proteins. We previously identified a novel human RNA binding protein, NF-kappaB binding protein (NFBP), which is the human homolog of Rrp5p, a protein component of the yeast U3 processome. Here, we show that NFBP colocalizes with and coprecipitates U3 in the nucleolus. We also demonstrate that NFBP is essential for the generation of 18S rRNA as maturation of the 18S rRNA is repressed in the absence of NFBP. Using Northern blot analyses, we further show that NFBP is specifically necessary for cleavages at sites A0, 1, and 2, as unprocessed intermediate forms of rRNA accumulated in the absence of NFBP.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ribosomas
/
ARN Ribosómico
/
Proteínas Nucleares
/
Procesamiento Postranscripcional del ARN
/
Proteínas de Unión al ARN
Límite:
Humans
Idioma:
En
Revista:
J Cell Physiol
Año:
2008
Tipo del documento:
Article
País de afiliación:
Estados Unidos