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Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells
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Protein transport across the endoplasmic reticulum membrane
1Howard Hughes Medical Institute and Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA. tom_rapoport@hms.harvard.edu
The FEBS Journal
|August 2, 2008
Summary
Protein translocation across membranes, crucial for eukaryotes and prokaryotes, occurs via the conserved Sec61/SecY complex. This protein-conducting channel facilitates transport and membrane protein integration.
Area of Science:
- Molecular biology
- Cell biology
- Biochemistry
Background:
- Protein translocation is essential for protein biogenesis in both eukaryotic and prokaryotic cells.
- Eukaryotic proteins are translocated across the endoplasmic reticulum membrane, while prokaryotic proteins cross the plasma membrane.
Discussion:
- The Sec61 (eukaryotes) and SecY (prokaryotes) complexes form a conserved, heterotrimeric protein-conducting channel.
- This channel is central to protein transport and membrane protein insertion.
- Structural and biochemical data reveal the channel's adaptability and function.
Key Insights:
- The Sec61/SecY complex acts as a universal protein-conducting channel.
- Mechanisms allow the channel to interact with diverse protein partners.
- The channel opens across the membrane and facilitates lateral release of hydrophobic segments.
Outlook:
- Further structural and biochemical studies will elucidate precise translocation mechanisms.
- Understanding these channels is key to deciphering protein biogenesis and membrane protein integration.
- Potential therapeutic targets may emerge from detailed knowledge of channel function.
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Targeting proteins to the ER
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