Faculty Opinions recommendation of Protein kinase D regulates vesicular transport by phosphorylating and activating phosphatidylinositol-4 kinase IIIbeta at the Golgi complex.

2005 ◽  
Author(s):  
Adam Linstedt
Keyword(s):  
Protein Kinase ◽  
Golgi Complex ◽  
Vesicular Transport ◽  
Protein Kinase D ◽  
Phosphatidylinositol 4

scholarly journals Protein kinase D regulates vesicular transport by phosphorylating and activating phosphatidylinositol-4 kinase IIIβ at the Golgi complex

2005 ◽  
Vol 7 (9) ◽  
pp. 880-886 ◽  
Author(s):  
Angelika Hausser ◽  
Peter Storz ◽  
Susanne Märtens ◽  
Gisela Link ◽  
Alex Toker ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Golgi Complex ◽  
Vesicular Transport ◽  
Protein Kinase D ◽  
Phosphatidylinositol 4

Impaired insulin exocytosis in chronic hepatitis C infection: contributory role of p38δ MAPK–protein kinase D–golgi complex axis

2020 ◽  
Vol 134 (12) ◽  
pp. 1449-1456
Author(s):  
Parimala Narne
Keyword(s):  
Hepatitis C ◽  
Protein Kinase ◽  
Golgi Complex ◽  
Hcv Infection ◽  
Protein Kinase D ◽  
Cell Dysfunction ◽  
Chronic Hcv Infection ◽  
Chronic Hcv ◽  
Insulin Exocytosis

Abstract Hepatitis C virus (HCV) infection and chronic hepatitis C (CHC) are associated with a measurable risk of insulin resistance (IR)/impaired glucose tolerance (IGT)/diabetes mellitus (DM). While loss of hepatic endocrine function contributes to liver cirrhosis in diabetic patients, onset and progression of IR/IGT to diabetes and exacerbation of incident hyperglycemia are ostensibly linked with chronic HCV infection. In this regard, the study by Chen J et al. appearing in Clinical Science (2020) (134(5) https://doi.org/10.1042/CS20190900) attempts to understand the mechanisms underlying the savaging effects of chronic HCV infection on insulin-producing pancreatic β-cells and hence diabetic onset. The study investigated the role of mitogen-activated protein kinase (MAPK) p38δ–protein kinase D (PKD)–golgi complex axis in impacting insulin exocytosis. It was inferred that an insulin secretory defect of pancreatic β-cells, owing to disrupted insulin exocytosis, to an extent explains β-cell dysfunction in HCV-infected or CHC milieu. HCV infection negatively regulates first-phase and second-phase insulin secretion by impinging on PKD-dependent insulin secretory granule fission at trans-golgi network and insulin secretory vesicle membrane fusion events. This commentary highlights the study in question, that deciphered the contribution of p38δ MAPK–PKD–golgi complex axis to β-cell dysfunction in CHC milieu. This pivotal axis proffers a formidable therapeutic opportunity for alleviation of double burden of glucose abnormalities/DM and CHC.

scholarly journals Protein Kinase D Controls the Integrity of Golgi Apparatus and the Maintenance of Dendritic Arborization in Hippocampal Neurons

2009 ◽  
Vol 20 (7) ◽  
pp. 2108-2120 ◽  
Author(s):  
Katalin Czöndör ◽  
Kornelia Ellwanger ◽  
Yannick F. Fuchs ◽  
Sylke Lutz ◽  
Márton Gulyás ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Golgi Complex ◽  
Hippocampal Neurons ◽  
Fluorescent Protein ◽  
Dendritic Tree ◽  
Secretory Vesicle ◽  
Dendritic Arborization ◽  
Dominant Negative ◽  
Protein Kinase D ◽  
Specific Expression

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 PKD1S738/742E (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 PKD1K612W (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.

scholarly journals Regulation of secretory transport by protein kinase D–mediated phosphorylation of the ceramide transfer protein

2007 ◽  
Vol 178 (1) ◽  
pp. 15-22 ◽  
Author(s):  
Tim Fugmann ◽  
Angelika Hausser ◽  
Patrik Schöffler ◽  
Simone Schmid ◽  
Klaus Pfizenmaier ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Lipid Transfer Protein ◽  
Membrane Integrity ◽  
Protein Kinase D ◽  
Lipid Transfer ◽  
Sphingomyelin Synthase ◽  
Transfer Protein ◽  
Secretory Transport ◽  
Phosphatidylinositol 4

Protein kinase D (PKD) has been identified as a crucial regulator of secretory transport at the trans-Golgi network (TGN). Recruitment and activation of PKD at the TGN is mediated by the lipid diacylglycerol, a pool of which is generated by sphingomyelin synthase from ceramide and phosphatidylcholine. The nonvesicular transfer of ceramide from the endoplasmic reticulum to the Golgi complex is mediated by the lipid transfer protein CERT (ceramide transport). In this study, we identify CERT as a novel in vivo PKD substrate. Phosphorylation on serine 132 by PKD decreases the affinity of CERT toward its lipid target phosphatidylinositol 4-phosphate at Golgi membranes and reduces ceramide transfer activity, identifying PKD as a regulator of lipid homeostasis. We also show that CERT, in turn, is critical for PKD activation and PKD-dependent protein cargo transport to the plasma membrane. Thus, the interdependence of PKD and CERT is key to the maintenance of Golgi membrane integrity and secretory transport.

scholarly journals Identification of Key Phospholipids That Bind and Activate Atypical PKCs

Biomedicines ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 45
Author(s):  
Suresh Velnati ◽  
Sara Centonze ◽  
Federico Girivetto ◽  
Daniela Capello ◽  
Ricardo M. Biondi ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phosphatidic Acid ◽  
Kinase Activity ◽  
Membrane Lipids ◽  
Atypical Protein Kinase C ◽  
Atypical Protein Kinase ◽  
Kinase C ◽  
Specific Regulation ◽  
Phosphatidylinositol 4

PKCζ and PKCι/λ form the atypical protein kinase C subgroup, characterised by a lack of regulation by calcium and the neutral lipid diacylglycerol. To better understand the regulation of these kinases, we systematically explored their interactions with various purified phospholipids using the lipid overlay assays, followed by kinase activity assays to evaluate the lipid effects on their enzymatic activity. We observed that both PKCζ and PKCι interact with phosphatidic acid and phosphatidylserine. Conversely, PKCι is unique in binding also to phosphatidylinositol-monophosphates (e.g., phosphatidylinositol 3-phosphate, 4-phosphate, and 5-phosphate). Moreover, we observed that phosphatidylinositol 4-phosphate specifically activates PKCι, while both isoforms are responsive to phosphatidic acid and phosphatidylserine. Overall, our results suggest that atypical Protein kinase C (PKC) localisation and activity are regulated by membrane lipids distinct from those involved in conventional PKCs and unveil a specific regulation of PKCι by phosphatidylinositol-monophosphates.

Sign in / Sign up

Export Citation Format

Share Document