Cyclin A-mediated inhibition of intra-Golgi transport requires p34cdc2.
An in vitro assay was used to study the role of p34cdc2 in cyclin A-mediated vesicular transport inhibition. It was shown that the S-phase kinase p33cdk2 reduced the effect of cyclin A on transport assays performed with sHeLa cytosol, even though histone kinase was strongly activated. Also, transport with FT210 cytosol (which is temperature-sensitive for p34cdc2) was inhibited by cyclin A only at the permissive temperature. However, the phosphatase inhibitor microcystin inhibited transport without any requirement for p34cdc2 activity. These results show that transport is inhibited by cyclin A via p34cdc2, and also by another kinase, possibly downstream of p34cdc2.
Mackay
D
D
Cell Biology Laboratory, Imperial Cancer Research Fund, London, UK.
Kieckbusch
R
R
Adamczewski
J
J
Warren
G
G
D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D016213:Cyclins / Q000494:pharmacology*; D003600:Cytosol / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D052998:Microcystins; D010456:Peptides, Cyclic / Q000494:pharmacology; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D006656:Protamine Kinase / Q000378:metabolism; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D019311:Staurosporine
D000470:Alkaloids; D016213:Cyclins; D052998:Microcystins; D010456:Peptides, Cyclic; C078588:microcystin; D006656:Protamine Kinase; D011493:Protein Kinase C; D016203:CDC2 Protein Kinase; D010749:Phosphoprotein Phosphatases; D019311:Staurosporine