A nuclear role for the DEAD-box protein Dbp5 in tRNA export.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31453808.
- Also identified by DOI 10.7554/eLife.48410 and PMC identifier 6711706.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Dbp5 is an essential DEAD-box protein that mediates nuclear mRNP export. Dbp5 also shuttles between nuclear and cytoplasmic compartments with reported roles in transcription, ribosomal subunit export, and translation; however, the mechanism(s) by which nucleocytoplasmic transport occurs and how Dbp5 specifically contributes to each of these processes remains unclear. Towards understanding the functions and transport of Dbp5 in <i>Saccharomyces cerevisiae</i>, alanine scanning mutagenesis was used to generate point mutants at all possible residues within a GFP-Dbp5 reporter. Characterization of the 456 viable mutants led to the identification of an N-terminal Xpo1-dependent nuclear export signal in Dbp5, in addition to other separation-of-function alleles, which together provide evidence that Dbp5 nuclear shuttling is not essential for mRNP export. Rather, disruptions in Dbp5 nucleocytoplasmic transport result in tRNA export defects, including changes in tRNA shuttling dynamics during recovery from nutrient stress.
Medical subject headings
- Biological Transport
- DEAD-box RNA Helicases
- Nucleocytoplasmic Transport Proteins
- RNA, Transfer
- Saccharomyces cerevisiae
- Saccharomyces cerevisiae Proteins