Yeast pre-rRNA processing and modification occur cotranscriptionally.

ABSTRACT: To better understand yeast ribosome synthesis, we developed techniques for the rapid harvesting and analysis of metabolically labeled cultures. Modeling of the resulting kinetic data allowed predicted lifetimes and processing patterns to be compared with the experimental data. This supported a transcription time for the 35S primary transcripts of approximately 170 s at 30 degrees C (approximately 40 nt s(-1)), with a high fraction (approximately 70%) of nascent transcripts cleaved at the early processing sites that generate the 20S precursor to the 18S rRNA. This level of nascent transcript cleavage apparently conflicted with previous reports that modification of yeast pre-rRNA exclusively occurred on released transcripts. A second round of high-resolution kinetic labeling showed that 20S

SUBMITTER: Kos M 

PROVIDER: S-EPMC2860240 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature