Podosome

Podosome
Code TH H1.00.01.1.02034

Podosomes are small cylindrical ECM adhesion structures approximately 0.5 um in diameter. They contain focal contact proteins like vinculin and paxillin and are found primarily in malignant cells. They can also be found in normal cells such as macrophages and osteoclasts. All podosomes contain gelsolin and dynamin proteins.[1]

They are the primary sites of integrin stimulated actin polymerization in leukocytes of the monocytic lineage. B cells have also been reported to form podosomes. Podosomes are similar in composition and structure to the invadopodia found in fibroblasts transformed with the v-Src oncogene which are matrix-degrading and whose formation is associated with increased tumor cell invasiveness.[2]

In myeloid cells, podosomes are necessary for directional movement and trans-cellular diapedesis at sites of inflammation.[3] In osteoclasts, podosomes are thought to aid in the creation of sealing rings associated with the area of bone resorption.

Unlike focal contacts in fibroblasts and epithelial cells, the formation of podosomes does not require protein synthesis.

See also

References

  1. ^ Geiger, B., Bershadsky, A., Pankov, Roumen., Yamada, M. (2001). "Transmembrane extracellular matrix - cytoskeleton crosstalk". Molecular cell biology 2: 793–805. 
  2. ^ Linder S (March 2007). "The matrix corroded: podosomes and invadopodia in extracellular matrix degradation". Trends Cell Biol. 17 (3): 107–17. doi:10.1016/j.tcb.2007.01.002. PMID 17275303. 
  3. ^ Calle Y, Burns S, Thrasher AJ, Jones GE (April 2006). "The leukocyte podosome". Eur. J. Cell Biol. 85 (3-4): 151–7. doi:10.1016/j.ejcb.2005.09.003. PMID 16546557. 

External links

Structures of the cell membrane
Membrane lipids
Membrane protein locations
Other
B memb: cead, trns (1A, 1C, 1F, 2A, 3A1, 3A2-3, 3D), othr