Limits...
RAF1-activated MEK1 is found on the Golgi apparatus in late prophase and is required for Golgi complex fragmentation in mitosis.

Colanzi A, Sutterlin C, Malhotra V - J. Cell Biol. (2003)

Bottom Line: Amitotically activated mitogen-activated protein kinase 1 (MEK1) fragments the pericentriolar Golgi stacks in mammalian cells.We show that activated MEK1 is found on the Golgi apparatus in late prophase.The fragmented and dispersed Golgi membranes in prometaphase and later stages of mitosis do not contain activated MEK1.

View Article: PubMed Central - PubMed

Affiliation: Cell and Developmental Biology Biology, University of California, San Diego, La Jolla, CA 92093-0347, USA.

ABSTRACT
Amitotically activated mitogen-activated protein kinase 1 (MEK1) fragments the pericentriolar Golgi stacks in mammalian cells. We show that activated MEK1 is found on the Golgi apparatus in late prophase. The fragmented and dispersed Golgi membranes in prometaphase and later stages of mitosis do not contain activated MEK1. MEK1-dependent Golgi complex fragmentation is through activation by RAF1 and not MEK1 kinase 1. We propose that a RAF1-dependent activation of MEK1 and its presence on the Golgi apparatus in late prophase is required for Golgi complex fragmentation.

Show MeSH

Related in: MedlinePlus

Intracellular distribution of activated MEK1 during mitosis. Cells were treated as described in Fig. 4 A and processed for confocal fluorescence microscopy by staining the Golgi apparatus, activated MEK1, and DNA with antibodies against β-COP, ppMEK, and the DNA-specific dye Hoechst, respectively.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2172875&req=5

fig5: Intracellular distribution of activated MEK1 during mitosis. Cells were treated as described in Fig. 4 A and processed for confocal fluorescence microscopy by staining the Golgi apparatus, activated MEK1, and DNA with antibodies against β-COP, ppMEK, and the DNA-specific dye Hoechst, respectively.

Mentions: The number of cells with Golgi complex localized activated MEK1 was quantified and the results are shown in Table I. About 83% of cells in late prophase exhibited Golgi complex–specific localization of mitotically activated MEK1. Cells at mitotic stages before or after late prophase did not contain mitotically activated MEK1 on Golgi membranes (Fig. 4 A and Fig. 5) . Together, these finding provide strong evidence that mitotically activated MEK1 is present on the Golgi membranes in late prophase.


RAF1-activated MEK1 is found on the Golgi apparatus in late prophase and is required for Golgi complex fragmentation in mitosis.

Colanzi A, Sutterlin C, Malhotra V - J. Cell Biol. (2003)

Intracellular distribution of activated MEK1 during mitosis. Cells were treated as described in Fig. 4 A and processed for confocal fluorescence microscopy by staining the Golgi apparatus, activated MEK1, and DNA with antibodies against β-COP, ppMEK, and the DNA-specific dye Hoechst, respectively.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2172875&req=5

fig5: Intracellular distribution of activated MEK1 during mitosis. Cells were treated as described in Fig. 4 A and processed for confocal fluorescence microscopy by staining the Golgi apparatus, activated MEK1, and DNA with antibodies against β-COP, ppMEK, and the DNA-specific dye Hoechst, respectively.
Mentions: The number of cells with Golgi complex localized activated MEK1 was quantified and the results are shown in Table I. About 83% of cells in late prophase exhibited Golgi complex–specific localization of mitotically activated MEK1. Cells at mitotic stages before or after late prophase did not contain mitotically activated MEK1 on Golgi membranes (Fig. 4 A and Fig. 5) . Together, these finding provide strong evidence that mitotically activated MEK1 is present on the Golgi membranes in late prophase.

Bottom Line: Amitotically activated mitogen-activated protein kinase 1 (MEK1) fragments the pericentriolar Golgi stacks in mammalian cells.We show that activated MEK1 is found on the Golgi apparatus in late prophase.The fragmented and dispersed Golgi membranes in prometaphase and later stages of mitosis do not contain activated MEK1.

View Article: PubMed Central - PubMed

Affiliation: Cell and Developmental Biology Biology, University of California, San Diego, La Jolla, CA 92093-0347, USA.

ABSTRACT
Amitotically activated mitogen-activated protein kinase 1 (MEK1) fragments the pericentriolar Golgi stacks in mammalian cells. We show that activated MEK1 is found on the Golgi apparatus in late prophase. The fragmented and dispersed Golgi membranes in prometaphase and later stages of mitosis do not contain activated MEK1. MEK1-dependent Golgi complex fragmentation is through activation by RAF1 and not MEK1 kinase 1. We propose that a RAF1-dependent activation of MEK1 and its presence on the Golgi apparatus in late prophase is required for Golgi complex fragmentation.

Show MeSH
Related in: MedlinePlus