To preserve epithelial barrier function, dying cells are squeezed out of an epithelium by "apoptotic cell extrusion." Specifically, a cell destined for apoptosis signals its live neighboring epithelial cells to form and contract a ring of actin and myosin II that squeezes the dying cell out of the epithelial sheet. Although most apoptotic cells extrude apically, we find that some exit basally. Localization of actin and myosin IIA contraction dictates the extrusion direction: basal extrusion requires circumferential contraction of neighboring cells at their apices, whereas apical extrusion also requires downward contraction along the basolateral surfaces. To activate actin/myosin basolaterally, microtubules in neighboring cells reorient and target p115 RhoGEF to this site. Preventing microtubule reorientation restricts contraction to the apex, driving extrusion basally. Extrusion polarity has important implications for tumors where apoptosis is blocked but extrusion is not, as basal extrusion could enable these cells to initiate metastasis.
Pubmed ID: 19720875 RIS Download
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Software tool for automated microscope acquisition, device control, and image analysis. Used for integrating dissimilar fluorescent microscope hardware and peripherals into a single custom workstation, while providing all the tools needed to perform analysis of acquired images. Offers user friendly application modules for analysis such as cell signaling, cell counting, and protein expression.
View all literature mentionsCell line MDCK is a Spontaneously immortalized cell line with a species of origin Canis lupus familiaris
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