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Updated: Jul 25, 2026
10:18
Analysis of Protein Import into Chloroplasts Isolated from Stressed Plants
Published on: November 1, 2016
The importance of importin.
1Dept of Cell and Molecular Biology, Northwestern University Medical School, Chicago, IL 60611, USA.
Trends in Cell Biology
|May 1, 1995
Summary
Nuclear protein import needs cytoplasmic factors. A Xenopus protein, homologous to yeast
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Nuclear protein import is essential for cell function.
- Cytoplasmic factors are required for the accumulation of karyophilic proteins in the nucleus.
- Cell-free systems have been instrumental in identifying these factors and understanding import mechanisms.
Purpose of the Study:
- To identify and characterize cytoplasmic factors involved in nuclear protein import.
- To define the biochemical requirements of the nuclear protein import process.
- To investigate the role of a specific purified and cloned factor from Xenopus.
Main Methods:
- Utilized cell-free systems to reconstitute nuclear protein import.
- Purified and cloned a specific cytoplasmic factor from Xenopus.
- Identified the Xenopus factor as a homologue of the yeast 'suppressor of RNA polymerase l' (SRP1) gene.
Main Results:
- Identified several cytoplasmic factors essential for nuclear protein import.
- Defined the biochemical requirements for nuclear import.
- Purified and cloned a Xenopus homologue of yeast SRP1, a key factor in nuclear transport.
- This factor belongs to a protein family potentially involved in similar nuclear transport functions.
Conclusions:
- Cytoplasmic factors are crucial for nuclear protein accumulation.
- The identified Xenopus SRP1 homologue plays a significant role in nuclear protein transport.
- This discovery suggests a conserved mechanism of nuclear protein transport across species.
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