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

Antonino Colanzi1, Christine Sutterlin, Vivek Malhotra

  • 1Cell and Developmental Biology Biology, University of California, San Diego, La Jolla, CA 92093-0347, USA.

The Journal of Cell Biology
|April 16, 2003
PubMed

Insights

Activated mitogen-activated protein kinase 1 (MEK1) fragments Golgi stacks during cell division. This process, dependent on RAF1 activation, occurs in late prophase for Golgi complex fragmentation.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • The Golgi apparatus undergoes significant structural changes during mitosis.
  • Mitogen-activated protein kinase 1 (MEK1) is a key signaling molecule involved in various cellular processes.

Purpose of the Study:

  • To investigate the role of MEK1 in Golgi complex fragmentation during mammalian cell mitosis.
  • To identify the upstream activators and localization of MEK1 during Golgi fragmentation.

Main Methods:

  • Immunofluorescence microscopy to detect activated MEK1 localization.
  • Analysis of Golgi structure during different stages of mitosis.
  • Investigating the role of RAF1 in MEK1 activation and Golgi fragmentation.

Main Results:

  • Activated MEK1 localizes to the Golgi apparatus in late prophase.
  • MEK1 is responsible for the fragmentation of Golgi stacks.
  • Golgi fragmentation is dependent on RAF1 activation of MEK1, not MEK1 kinase activity.

Conclusions:

  • RAF1-dependent activation and Golgi localization of MEK1 are essential for Golgi complex fragmentation during mitosis.
  • MEK1 plays a critical role in regulating Golgi structure dynamics during cell division.

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