title: Protein kinase A activity is necessary for fission and fusion of Golgi to endoplasmic reticulum retrograde tubules.
abstract: It is becoming increasingly accepted that together with vesicles, tubules play a major role in the transfer of cargo between different cellular compartments. In contrast to our understanding of the molecular mechanisms of vesicular transport, little is known about tubular transport. How signal transduction molecules regulate these two modes of membrane transport processes is also poorly understood. In this study we investigated whether protein kinase A (PKA) activity regulates the retrograde, tubular transport of Golgi matrix proteins from the Golgi to the endoplasmic reticulum (ER). We found that Golgi-to-ER retrograde transport of the Golgi matrix proteins giantin, GM130, GRASP55, GRASP65, and p115 was impaired in the presence of PKA inhibitors. In addition, we unexpectedly found accumulation of tubules containing both Golgi matrix proteins and resident Golgi transmembrane proteins. These tubules were still attached to the Golgi and were highly dynamic. Our data suggest that both fission and fusion of retrograde tubules are mechanisms regulated by PKA activity.
authors.affiliation: Instituto de Fisiología, Facultad de Medicina, and Centro Interdisciplinario de Estudios del Sistema Nerviso, Universidad Austral de Chile, Valdivia, Chile.
authors.forename: María J
authors.initials: MJ
authors.lastname: Tenorio
authors.affiliation: Instituto de Fisiología, Facultad de Medicina, and Centro Interdisciplinario de Estudios del Sistema Nerviso, Universidad Austral de Chile, Valdivia, Chile.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Luchsinger
authors.affiliation: Instituto de Fisiología, Facultad de Medicina, and Centro Interdisciplinario de Estudios del Sistema Nerviso, Universidad Austral de Chile, Valdivia, Chile.
authors.forename: Gonzalo A
authors.initials: GA
authors.lastname: Mardones
mesh_terms: D000818:Animals; D001324:Autoantigens / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D002460:Cell Line; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D015870:Gene Expression; D006056:Golgi Apparatus / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D000077614:Golgi Matrix Proteins; D006367:HeLa Cells; D006801:Humans; D061986:MCF-7 Cells; D008561:Membrane Fusion / Q000187:drug effects / Q000502:physiology; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D051381:Rats; D015398:Signal Transduction; D059008:Time-Lapse Imaging; D022161:Transport Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D001324:Autoantigens; C108705:GORASP1 protein, human; C122048:GORASP2 protein, human; D000077614:Golgi Matrix Proteins; C097741:Golgin subfamily A member 2; D008565:Membrane Proteins; D047428:Protein Kinase Inhibitors; D033921:Vesicular Transport Proteins; C087574:macrogolgin; C091580:vesicular transport factor p115; D017868:Cyclic AMP-Dependent Protein Kinases