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P5-ATPases: Structure, substrate specificities, and transport mechanisms
1Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.
Current Opinion in Structural Biology
|February 1, 2023
Summary
P5-ATPases transport substrates in the endoplasmic reticulum and endo-/lysosomes. Recent studies reveal their unique mechanisms for extracting transmembrane helices and exporting polyamines.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- P5-ATPases are eukaryotic ATP-dependent transporters crucial for endoplasmic reticulum (ER) and endo-/lysosomal function.
- Their specific substrates and transport mechanisms were previously unknown.
- They belong to the P-type ATPase superfamily but exhibit distinct characteristics.
Purpose of the Study:
- To elucidate the substrate specificities and transport mechanisms of P5A- and P5B-ATPases.
- To understand how P5-ATPases differ from other P-type ATPases.
- To review recent structural and biochemical findings on P5-ATPases.
Main Methods:
- Cryo-electron microscopy (cryo-EM) studies of yeast and human P5-ATPases.
- Biochemical analyses of P5-ATPase function.
- Structural analysis of P5-ATPase transmembrane domains.
Main Results:
- P5A-ATPases extract mis-inserted transmembrane helices from the ER membrane for protein quality control.
- P5B-ATPases export polyamines from late endo-/lysosomes to the cytosol.
- P5-ATPases exhibit unique substrate recognition and transport mechanisms compared to other P-type ATPases.
Conclusions:
- Structural diversification, particularly in the transmembrane domain, allows P5-ATPases to transport atypical substrates.
- These findings provide new insights into protein quality control and cellular transport processes.
- P5-ATPases represent a specialized subfamily of ATP-dependent transporters with unique biological roles.
Keywords:
Endoplasmic reticulumKufor Rakeb syndromeLysosomesP-type ATPasesP5-ATPasesParkinson's diseasePolyamineProtein quality controlTail-anchored membrane proteinsMore Related Videos
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