Rhabdomere biogenesis in Drosophila photoreceptors is acutely sensitive to phosphatidic acid levels.
Phosphatidic acid (PA) is postulated to have both structural and signaling functions during membrane dynamics in animal cells. In this study, we show that before a critical time period during rhabdomere biogenesis in Drosophila melanogaster photoreceptors, elevated levels of PA disrupt membrane transport to the apical domain. Lipidomic analysis shows that this effect is associated with an increase in the abundance of a single, relatively minor molecular species of PA. These transport defects are dependent on the activation state of Arf1. Transport defects via PA generated by phospholipase D require the activity of type I phosphatidylinositol (PI) 4 phosphate 5 kinase, are phenocopied by knockdown of PI 4 kinase, and are associated with normal endoplasmic reticulum to Golgi transport. We propose that PA levels are critical for apical membrane transport events required for rhabdomere biogenesis.
Inositide Laboratory, Babraham Institute, Babraham Research Campus, Cambridge, England, UK. raghu.padinjat@bbsrc.ac.uk
Padinjat
P
Raghu
Elise
E
Coessens
Maria
M
Manifava
Plamen
P
Georgiev
Trevor
T
Pettitt
Eleanor
E
Wood
Isaac
I
Garcia-Murillas
Hanneke
H
Okkenhaug
Deepti
D
Trivedi
Qifeng
Q
Zhang
Azam
A
Razzaq
Ola
O
Zaid
Michael
M
Wakelam
Cahir J
CJ
O'Kane
Nicholas
N
Ktistakis
D019870:1-Phosphatidylinositol 4-Kinase / Q000037:antagonists & inhibitors / Q000502:physiology; D020823:ADP-Ribosylation Factor 1 / Q000502:physiology; D000089982:ADP-Ribosylation Factor 6; D020727:ADP-Ribosylation Factors / Q000502:physiology; D033965:Adaptor Protein Complex alpha Subunits / Q000037:antagonists & inhibitors / Q000502:physiology; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D002798:Diacylglycerol Cholinephosphotransferase / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development / Q000648:ultrastructure*; D034281:Dynamins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D008563:Membrane Lipids / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D010641:Phenotype; D010711:Phosphatidate Phosphatase / Q000235:genetics / Q000378:metabolism; D010712:Phosphatidic Acids / Q000378:metabolism*; D010739:Phospholipase D / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D010786:Photoreceptor Cells / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure*; D034622:RNA Interference
D000089982:ADP-Ribosylation Factor 6; D033965:Adaptor Protein Complex alpha Subunits; D029721:Drosophila Proteins; D008563:Membrane Lipids; D010712:Phosphatidic Acids; D017853:Phosphotransferases (Alcohol Group Acceptor); D019870:1-Phosphatidylinositol 4-Kinase; C020077:1-phosphatidylinositol-4-phosphate 5-kinase; D002798:Diacylglycerol Cholinephosphotransferase; C406242:phosphatidic acid phosphatase type 2; D010711:Phosphatidate Phosphatase; D010739:Phospholipase D; D020823:ADP-Ribosylation Factor 1; D020727:ADP-Ribosylation Factors; D034281:Dynamins; C439628:shi protein, Drosophila