Protein kinase D controls the integrity of Golgi apparatus and the maintenance of dendritic arborization in hippocampal neurons.
Protein kinase D (PKD) is known to participate in various cellular functions, including secretory vesicle fission from the Golgi and plasma membrane-directed transport. Here, we report on expression and function of PKD in hippocampal neurons. Expression of an enhanced green fluorescent protein (EGFP)-tagged PKD activity reporter in mouse embryonal hippocampal neurons revealed high endogenous PKD activity at the Golgi complex and in the dendrites, whereas PKD activity was excluded from the axon in parallel with axonal maturation. Expression of fluorescently tagged wild-type PKD1 and constitutively active PKD1(S738/742E) (caPKD1) in neurons revealed that both proteins were slightly enriched at the trans-Golgi network (TGN) and did not interfere with its thread-like morphology. By contrast, expression of dominant-negative kinase inactive PKD1(K612W) (kdPKD1) led to the disruption of the neuronal Golgi complex, with kdPKD1 strongly localized to the TGN fragments. Similar findings were obtained from transgenic mice with inducible, neuron-specific expression of kdPKD1-EGFP. As a prominent consequence of kdPKD1 expression, the dendritic tree of transfected neurons was reduced, whereas caPKD1 increased dendritic arborization. Our results thus provide direct evidence that PKD activity is selectively involved in the maintenance of dendritic arborization and Golgi structure of hippocampal neurons.
Czöndör
Katalin
K
Department of Physiology and Neurobiology, Eötvös Loránd University, Budapest, Hungary H-1117.
Ellwanger
Kornelia
K
Fuchs
Yannick F
YF
Lutz
Sylke
S
Gulyás
Márton
M
Mansuy
Isabelle M
IM
Hausser
Angelika
A
Pfizenmaier
Klaus
K
Schlett
Katalin
K
D000818:Animals; D002451:Cell Compartmentation / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D016764:Cell Polarity / Q000187:drug effects; D003712:Dendrites / Q000187:drug effects / Q000201:enzymology*; D004318:Doxycycline / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D005799:Genes, Dominant; D017930:Genes, Reporter; D006056:Golgi Apparatus / Q000187:drug effects / Q000201:enzymology*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology*; D006801:Humans; D051379:Mice; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D011493:Protein Kinase C / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014162:Transfection; D021601:trans-Golgi Network / Q000187:drug effects / Q000201:enzymology
D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; C089212:protein kinase D; D011493:Protein Kinase C; D004318:Doxycycline