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Rab35 Targeting to the Plasma Membrane Is Dependent on the C-terminal Polybasic Cluster
Katsuhisa Kawai1, Youhei Egami1, Arata Nishigaki1
1Department of Histology and Cell Biology, School of Medicine, Kagawa University, Miki, Kagawa 761-0793, Japan.
Acta Histochemica Et Cytochemica
|September 3, 2020
Summary
The C-terminal region of Rab35, specifically a basic amino acid cluster, dictates its plasma membrane localization. Altering this cluster shifts Rab35
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Trafficking
Background:
- Rab35, a Rab GTPase, participates in cell motility and membrane trafficking.
- Rab proteins with high sequence homology to Rab35 display varied subcellular localizations.
- A distinct ~30-amino acid C-terminal region variation exists among Rab35 family members.
Purpose of the Study:
- To investigate the role of the C-terminal region in Rab35 subcellular localization.
- To determine if the C-terminus dictates plasma membrane targeting.
- To elucidate the contribution of basic amino acids within the C-terminus to Rab35 localization.
Main Methods:
- Amino acid sequence comparison between Rab35 and homologous Rab proteins.
- Construction of Rab35-Rab10 chimera proteins by exchanging C-terminal domains.
- Confocal microscopy analysis of EGFP-fused chimera localization in RAW264 cells.
Main Results:
- The C-terminal domain of Rab35 is crucial for its localization to the plasma membrane.
- A cluster of basic amino acids is identified within Rab35's C-terminus.
- Reducing basic amino acids in the C-terminus causes Rab35 to localize to the Golgi membrane.
Conclusions:
- The ~30-amino acid C-terminal region, containing basic clusters, governs Rab35 plasma membrane localization.
- The number of basic amino acids in this region influences Rab35's preferential localization.
- This region acts as a key determinant for Rab35's specific subcellular targeting.
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