title: 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.
abstract: 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.
authors.affiliation: Department of Internal Medicine I, University of Ulm, Ulm 89081, Germany.
authors.forename: Ganesh Varma
authors.initials: GV
authors.lastname: Pusapati
authors.forename: Denis
authors.initials: D
authors.lastname: Krndija
authors.forename: Milena
authors.initials: M
authors.lastname: Armacki
authors.forename: Götz
authors.initials: G
authors.lastname: von Wichert
authors.forename: Julia
authors.initials: J
authors.lastname: von Blume
authors.forename: Vivek
authors.initials: V
authors.lastname: Malhotra
authors.forename: Guido
authors.initials: G
authors.lastname: Adler
authors.forename: Thomas
authors.initials: T
authors.lastname: Seufferlein
mesh_terms: 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*
chemical_list: D007527:Isoenzymes; D000091283:Protein Kinase D2; D011993:Recombinant Fusion Proteins; D011392:Proline; D011494:Protein Kinases; D020823:ADP-Ribosylation Factor 1