Supplemental Material

This article contains the following supporting material:

• Movie 1 - Podosome dynamics and membrane protrusions in osteoclasts expressing control scrambled RNAi.
  Phase-contrast images of cells at 37°C were collected every 10 sec for 5 min. Movie is shown at a rate of 8 frames/sec. Podosomes are seen immediately adjacent to the protruding membrane.

• Movie 2 - Absence of podosomes in osteoclasts expressing cortactin knockdown RNAi sequence #2.
  Phase-contrast images of cells at 37°C were collected every 10 sec for 5 min. Movie is shown at a rate of 8 frames/sec. No podosome belts are observed, but membrane protrusions are evident. Phase-light and phase-dark vesicles are seen behind the cell edge, presumably secondary to macropinocytosis and endocytosis.

• Movie 3 - Dynamics of podosome belts in area with two belts.
  A belt of podosomes at the cell edge disappears and a new belt appears, farther back from the edge. Phase-contrast images of cells at 37°C were collected every 10 sec for 5 min. Movie is shown at a rate of 8 frames/sec.