Dimeric PKD regulates membrane fission to form transport carriers at the TGN

Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093, USA.
The Journal of Cell Biology (Impact Factor: 9.83). 01/2008; 179(6):1123-31. DOI: 10.1083/jcb.200703166
Source: PubMed


Protein kinase D (PKD) is recruited to the trans-Golgi network (TGN) through interaction with diacylglycerol (DAG) and is required for the biogenesis of TGN to cell surface transport carriers. We now provide definitive evidence that PKD has a function in membrane fission. PKD depletion by siRNA inhibits trafficking from the TGN, whereas expression of a constitutively active PKD converts TGN into small vesicles. These findings demonstrate that PKD regulates membrane fission and this activity is used to control the size of transport carriers, and to prevent uncontrolled vesiculation of TGN during protein transport.

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