MOVIE S2. Normal clearance of murine respiratory tract is mediated by discontinuous Muc5b and Muc5ac mucus clouds

<p>Movie S2. Mucus-trapped beads moves slower than free beads. Mouse trachea was mounted and submerged in a buffer containing Alcian blue and 1 &micro;m fluorescent beads, the tissue tilted, and the movement of mucus and beads recorded by video microscopy.</p>