February 7, 2013

The alphabet soup of cell biology can be overwhelming, but APC is one jumble of letters that most cell biologists are very familiar with.  APC is a protein that functions in cell division and development, and is the most commonly mutated gene in colon cancer.  Today’s image is from a paper describing another hat that APC gets to wear—a role in the interaction between microtubules and intermediate filaments.

Intermediate filaments (IFs) and microtubules are both part of the cell’s cytoskeleton, and their interactions together during different cellular processes have brought attention to the possible proteins that guide these interactions.  IFs function in cell migration, and a recent paper describes rearrangements of the IF network during the migration of astrocytes, cells that provide nutritional and structural support for neurons in the brain.  Sakamoto and colleagues found that the tumor suppressor protein APC (adenomatous polyposis coli) is required for microtubule-IF interactions and for the microtubule-based rearrangements of the IF network in migrating astrocytes.  Loss of APC resulted in a disorganized IF network in glioma and carcinoma cells.  The images above show microtubule-APC-IF interactions in a migrating astrocyte, with fluorescently labeled IFs (vimentin, green), APC (red), and microtubules (blue).  Arrowheads point to APC along microtubules, while arrows point to both IFs and APC along microtubules.

Sakamoto, Y., Boeda, B., & Etienne-Manneville, S. (2013). APC binds intermediate filaments and is required for their reorganization during cell migration originally published in the Journal of Cell Biology, 200 (3), 249-258 DOI: 10.1083/jcb.201206010