These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: A U3 small nuclear ribonucleoprotein-requiring processing event in the 5' external transcribed spacer of Xenopus precursor rRNA. Author: Mougey EB, Pape LK, Sollner-Webb B. Journal: Mol Cell Biol; 1993 Oct; 13(10):5990-8. PubMed ID: 8413202. Abstract: A processing site has been identified within the 5' external transcribed spacer (ETS) of Xenopus laevis and X. borealis pre-RNAs, and this in vivo processing can be reproduced in vitro. It involves a stable and specific association of the pre-rRNA with factors in the cell extract, including at least four RNA-contacting polypeptides, yielding a distinct complex that sediments at 20S. Processing also requires the U3 small nuclear RNA. This processing, at residue +105 of the 713-nucleotide X. laevis 5' ETS, is highly reminiscent of the initial processing cleavage of mouse pre-rRNA within its 3.5-kb 5' ETS, previously thought to be mammal specific. The frog and mouse processing signals share a short essential sequence motif, and mouse factors can faithfully process the frog pre-rRNA. This conservation suggests that this 5' ETS processing site serves an evolutionarily selective function.[Abstract] [Full Text] [Related] [New Search]