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Inhibition of Golgi function causes plastid starch accumulation
Eric Hummel1, Anne Osterrieder, David G Robinson
1School of Life Sciences, Oxford Brookes University, Oxford, UK. eric.hummel@uni-bayreuth.de
Journal of Experimental Botany
|April 29, 2010
Summary
Blocking secretory pathways causes starch accumulation in chloroplasts, suggesting a direct link between Golgi apparatus activity and plastid function. This highlights a novel interaction impacting plant cell metabolism.
Area of Science:
- Plant cell biology
- Organelle interactions
- Protein transport
Background:
- The interaction between chloroplasts and the Golgi apparatus is poorly understood.
- Evidence suggests a Golgi-to-chloroplast protein transport pathway exists.
- This pathway targets proteins to chloroplast membranes and stroma.
Purpose of the Study:
- To investigate the functional interaction between chloroplasts and the Golgi apparatus.
- To determine if Golgi activity influences starch accumulation in plastids.
Main Methods:
- Inhibiting the secretory pathway using brefeldin A.
- Inducing Golgi disassembly via an inducible Sar1-GTP system.
- Observing starch accumulation within chloroplasts.
Main Results:
- Blocking secretion led to significant starch accumulation in chloroplasts.
- Golgi disassembly, induced by brefeldin A or Sar1-GTP, caused dramatic starch accumulation.
- These findings provide evidence for direct interaction between Golgi activity and plastids.
Conclusions:
- Golgi apparatus activity directly impacts starch accumulation in chloroplasts.
- Disruption of secretory pathways affects plastid function.
- Further research is needed to elucidate the precise mechanisms, including potential roles of cytosolic sugars or amylase transport.
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