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Purification of Extracellular Trypanosomes, Including African, from Blood by Anion-Exchangers Diethylaminoethyl-cellulose Columns
Published on: April 6, 2019
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Stage-Specific COPII-Mediated Cargo Selectivity in African Trypanosomes
Mohamed Sharif1, James D Bangs2
1Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA.
Msphere
|June 21, 2022
Summary
African trypanosomes alter their COPII vesicle transport machinery between life stages. Selectivity for GPI-anchored protein export is lost in insect stage parasites, impacting protein trafficking.
Area of Science:
- Cell Biology
- Molecular Biology
- Parasitology
Background:
- Eukaryotic cells utilize a secretory pathway for intracellular transport, with COPII-coated vesicles mediating ER to Golgi transport.
- African trypanosomes possess stage-specific secretory pathways crucial for their parasitic life cycle and surface coat synthesis.
Purpose of the Study:
- To investigate the functional differences in COPII vesicle coat complex assembly and cargo selectivity between bloodstream and insect stages of African trypanosomes.
- To determine the essentiality and specific roles of Sec23/24 paralogs in COPII transport in procyclic insect-form trypanosomes.
Main Methods:
- RNA interference (RNAi) knockdowns were employed to assess the essentiality of TbSec23 and TbSec24 isoforms in procyclic trypanosomes.
- Analysis of cargo trafficking, including glycosylphosphatidylinositol-anchored proteins (GPI-APs) and lysosomal proteins, following RNAi silencing.
Main Results:
- All TbSec23 and TbSec24 isoforms are essential for procyclic trypanosome survival.
- Loss of cargo selectivity for GPI-APs was observed in insect-stage parasites compared to bloodstream-stage parasites.
- Silencing of the TbSec23.2/TbSec24.1 heterodimer significantly impacted the trafficking of soluble proteins like TbCatL.
Conclusions:
- COPII-mediated transport selectivity is altered between bloodstream and insect stages of African trypanosomes, suggesting adaptation to their digenetic life cycle.
- These findings highlight stage-specific adaptations in the secretory pathway of African trypanosomes, impacting surface protein dynamics and host-parasite interactions.
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