TY - JOUR
T1 - The U3 small nucleolar ribonucleoprotein functions in the first step of preribosomal RNA processing
AU - Kass, Susan
AU - Tyc, Kazimierz
AU - Steitz, Joan A.
AU - Sollner-Webb, Barbara
N1 - Funding Information:
We are indebted to Alan Weiner and members of the Steitz and Sollner-Webb labs for comments on the manuscript. Drs. G. Reimer, E. Tan, and R. Sontheimer generously provided the anti-fibrillarin antibodies and Drs. llana Stroke and Alan Weiner provided the U3 clone. We also thank Nadine Qashu for technical assistance and Lynda Stevens and Margaret Minnek for assistance in preparing the manuscript. This work was supported by ACS grant NP-731A to B. S. and PHF grant GM26154 to J. A. S.
PY - 1990/3/23
Y1 - 1990/3/23
N2 - The first cleavage in mammalian pre-rRNA maturation occurs near the 5′ end within the 5′ external transcribed spacer. Using mouse cell extracts, we show that this processing is abolished by micrococcal nuclease pretreatment. Autoantibodies that recognize the U3, U8, and U13 snRNPs (anti-fibrillarin) deplete processing activity from the extract and selectively immunoprecipitate both rRNA substrates and processing products from the reaction. Specific involvement of the U3 snRNP is demonstrated by native gel electrophoresis of the processing reaction followed by Northern blotting and by oligonucleotide-directed RNA-ase H abolition of processing activity. Our identification of U3 function is discussed with respect to the molecular basis of pre-rRNA recognition by the U3 snRNP, possible roles of U3 and other nucleolar snRNPs in rRNA processing, and the morphological organization of the nucleolus and the ribosomal transcription complex.
AB - The first cleavage in mammalian pre-rRNA maturation occurs near the 5′ end within the 5′ external transcribed spacer. Using mouse cell extracts, we show that this processing is abolished by micrococcal nuclease pretreatment. Autoantibodies that recognize the U3, U8, and U13 snRNPs (anti-fibrillarin) deplete processing activity from the extract and selectively immunoprecipitate both rRNA substrates and processing products from the reaction. Specific involvement of the U3 snRNP is demonstrated by native gel electrophoresis of the processing reaction followed by Northern blotting and by oligonucleotide-directed RNA-ase H abolition of processing activity. Our identification of U3 function is discussed with respect to the molecular basis of pre-rRNA recognition by the U3 snRNP, possible roles of U3 and other nucleolar snRNPs in rRNA processing, and the morphological organization of the nucleolus and the ribosomal transcription complex.
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U2 - 10.1016/0092-8674(90)90338-F
DO - 10.1016/0092-8674(90)90338-F
M3 - Article
C2 - 2156625
AN - SCOPUS:0025276512
SN - 0092-8674
VL - 60
SP - 897
EP - 908
JO - Cell
JF - Cell
IS - 6
ER -