Phospholipase D activity couples plasma membrane endocytosis with retromer dependent recycling
- National Centre for Biological Sciences, India
- Babraham Institute, United Kingdom
Abstract
During illumination, the light sensitive plasma membrane (rhabdomere) of Drosophila photoreceptors undergoes turnover with consequent changes in size and composition. However the mechanism by which illumination is coupled to rhabdomere turnover remains unclear. We find that photoreceptors contain a light-dependent phospholipase D (PLD) activity. During illumination, loss of PLD resulted in an enhanced reduction in rhabdomere size, accumulation of Rab7 positive, rhodopsin1-containing vesicles (RLVs) in the cell body and reduced rhodopsin protein. These phenotypes were associated with reduced levels of phosphatidic acid, the product of PLD activity and were rescued by reconstitution with catalytically active PLD. In wild type photoreceptors, during illumination, enhanced PLD activity was sufficient to clear RLVs from the cell body by a process dependent on Arf1-GTP levels and retromer complex function. Thus, during illumination, PLD activity couples endocytosis of RLVs with their recycling to the plasma membrane thus maintaining plasma membrane size and composition.
Article and author information
Author details
Nicholas T Ktistakis
Funding
Wellcome Trust DBT India Alliance (IA/S/14/2/501540)
- Rajan Thakur
- Nikita Raj
- Shweta Yadav
- Sruthi Balakrishnan
- Bishal Basak
- Raghu Padinjat
National Centre for Biological Sciences (core)
- Rajan Thakur
- Aniruddha Panda
- Nikita Raj
- Shweta Yadav
- Sruthi Balakrishnan
- Bishal Basak
- Renu Pasricha
- Raghu Padinjat
Department of Biotechnology , Ministry of Science and Technology (BT/PR4833/MED/30/744/2012)
- Rajan Thakur
- Aniruddha Panda
- Nikita Raj
- Shweta Yadav
- Sruthi Balakrishnan
- Bishal Basak
- Renu Pasricha
- Raghu Padinjat
Biotechnology and Biological Sciences Research Council (core)
- Elise Coessens
- Qifeng Zhang
- Plamen Georgiev
- Michael JO Wakelam
- Nicholas T Ktistakis
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Thakur et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Phospholipase D activity couples plasma membrane endocytosis with retromer dependent recycling
eLife 5:e18515.
https://doi.org/10.7554/eLife.18515
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