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Analysis of mRNA Nuclear Export Kinetics in Mammalian Cells by Microinjection
11:32

Analysis of mRNA Nuclear Export Kinetics in Mammalian Cells by Microinjection

Published on: December 4, 2010

Mex67p mediates nuclear export of a variety of RNA polymerase II transcripts

E Hurt1, K Strässer, A Segref

  • 1University of Heidelberg, BZH, Im Neuenheimer Feld 328, D-69120 Heidelberg, Germany. cg5@ix.urz.uni-heidelberg.de

The Journal of Biological Chemistry
|March 18, 2000
PubMed

Insights

Mex67p protein is crucial for exporting heat shock mRNAs and other essential transcripts from the nucleus in yeast. This ensures proper protein production after cellular stress.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Genetics

Background:

  • Mex67p is known to be essential for nuclear poly(A)(+) RNA export in yeast.
  • The specific transcripts regulated by Mex67p have not been identified.

Purpose of the Study:

  • To investigate the role of Mex67p in the nuclear export of specific RNA transcripts, particularly heat shock mRNAs.
  • To determine if Mex67p facilitates the export of a broader range of polymerase II transcripts.

Main Methods:

  • Utilized thermosensitive mex67-5 yeast cells to analyze heat shock response.
  • Employed in situ hybridization with fluorescent-labeled oligonucleotide probes to track nuclear export of heat shock mRNAs (e.g., SSA transcripts).

Main Results:

  • Thermosensitive mex67-5 cells failed to mount a heat shock response at restrictive temperatures but showed delayed induction upon return to permissive temperatures.
  • Mex67p was found to be essential for the nuclear export of heat shock mRNAs.
  • Nuclear export of other polymerase II transcripts, including ASH1 and PGK1 mRNAs, also requires Mex67p.

Conclusions:

  • Mex67p plays a critical role in the nuclear export of heat shock mRNAs, explaining the observed 'memory' effect in mex67-5 cells.
  • Mex67p functions as a general mRNA export factor for a diverse set of polymerase II transcripts in yeast.

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