Role of the second cysteine-rich domain and Pro275 in protein kinase D2 interaction with ADP-ribosylation factor 1, trans-Golgi network recruitment, and protein transport.
Protein kinase D (PKD) isoenzymes regulate the formation of transport carriers from the trans-Golgi network (TGN) that are en route to the plasma membrane. The PKD C1a domain is required for the localization of PKDs at the TGN. However, the precise mechanism of how PKDs are recruited to the TGN is still elusive. Here, we report that ADP-ribosylation factor (ARF1), a small GTPase of the Ras superfamily and a key regulator of secretory traffic, specifically interacts with PKD isoenzymes. ARF1, but not ARF6, binds directly to the second cysteine-rich domain (C1b) of PKD2, and precisely to Pro275 within this domain. Pro275 in PKD2 is not only crucial for the PKD2-ARF1 interaction but also for PKD2 recruitment to and PKD2 function at the TGN, namely, protein transport to the plasma membrane. Our data suggest a novel model in which ARF1 recruits PKD2 to the TGN by binding to Pro275 in its C1b domain followed by anchoring of PKD2 in the TGN membranes via binding of its C1a domain to diacylglycerol. Both processes are critical for PKD2-mediated protein transport.
Pusapati
Ganesh Varma
GV
Department of Internal Medicine I, University of Ulm, Ulm 89081, Germany.
Krndija
Denis
D
Armacki
Milena
M
von Wichert
Götz
G
von Blume
Julia
J
Malhotra
Vivek
V
Adler
Guido
G
Seufferlein
Thomas
T
D020823:ADP-Ribosylation Factor 1 / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D011392:Proline / Q000378:metabolism*; D000091283:Protein Kinase D2; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000502:physiology*; D034622:RNA Interference; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D021601:trans-Golgi Network / Q000378:metabolism*
D007527:Isoenzymes; D000091283:Protein Kinase D2; D011993:Recombinant Fusion Proteins; D011392:Proline; D011494:Protein Kinases; D020823:ADP-Ribosylation Factor 1