We report the characterization of a novel factor, Nob1p (Yor056c), which is essential for the synthesis of 40S ribosome subunits. Genetic depletion of Nob1p strongly inhibits the processing of the 20S pre-rRNA to the mature 18S rRNA, leading to the accumulation of high levels of the 20S pre-rRNA together with novel degradation intermediates. 20S processing occurs within a pre-40S particle after its export from the nucleus to the cytoplasm. Consistent with a direct role in this cleavage, Nob1p was shown to be associated with the pre-40S particle and to be present in both the nucleus and the cytoplasm. This suggests that Nob1p accompanies the pre-40S ribosomes during nuclear export. Pre-40S export is not, however, inhibited by depletion of Nob1p.
Nob1p is required for cleavage of the 3’ end of the 18S rRNA / Fatica, Alessandro; Oeffinger, M.; Dlakic, M.; Tollervey, D.. - In: MOLECULAR AND CELLULAR BIOLOGY. - ISSN 0270-7306. - STAMPA. - 23:(2003), pp. 1798-1807. [10.1128/MCB.23.5.1798-1807.2003]
Nob1p is required for cleavage of the 3’ end of the 18S rRNA.
FATICA, Alessandro;
2003
Abstract
We report the characterization of a novel factor, Nob1p (Yor056c), which is essential for the synthesis of 40S ribosome subunits. Genetic depletion of Nob1p strongly inhibits the processing of the 20S pre-rRNA to the mature 18S rRNA, leading to the accumulation of high levels of the 20S pre-rRNA together with novel degradation intermediates. 20S processing occurs within a pre-40S particle after its export from the nucleus to the cytoplasm. Consistent with a direct role in this cleavage, Nob1p was shown to be associated with the pre-40S particle and to be present in both the nucleus and the cytoplasm. This suggests that Nob1p accompanies the pre-40S ribosomes during nuclear export. Pre-40S export is not, however, inhibited by depletion of Nob1p.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
