Fragments of the internal transcribed spacer 1 of pre-rRNA accumulate in Saccharomyces cerevisiae lacking 5'----3' exoribonuclease 1.
The portion of the internal transcribed spacer 1 found on 20S pre-rRNA accumulates in Saccharomyces cerevisiae lacking 5'----3' exoribonuclease 1, showing that an endonucleolytic cleavage at the 3' terminus of 18S rRNA is involved in the 20S pre-rRNA to 18S mature rRNA conversion. Smaller fragments of the spacer sequence are also found. The exoribonuclease may be involved as a cytoplasmic RNase in the hydrolysis of the spacer.
Stevens
A
A
Biology Division, Oak Ridge National Laboratory, Tennessee 37831-8077.
Hsu
C L
CL
Isham
K R
KR
Larimer
F W
FW
D005095:Exoribonucleases / Q000378:metabolism*; D012322:RNA Precursors / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012337:RNA, Ribosomal, 18S / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*
D012322:RNA Precursors; D012337:RNA, Ribosomal, 18S; D005095:Exoribonucleases; C022535:exoribonuclease II