Abrupt tissue contraction and actomyosin cable formation initiate wound healing.

<p><b>A–D</b> Sequential images of a representative <i>in vivo</i> 55 min time-lapse movie of an Utrophin-GFP mRNA-injected 2 dpf larva at different time-points after amputation. <b>A</b> At 5minpa, there is accumulation of actin at the leading edge cells. <b>B</b> By 8 minpa the actin cable is assembled (arrow) and there is tissue contraction - note displacement of arrowheads in comparison with A. <b>C</b> At 30 minpa, the tissue has fully contracted. <b>D</b> At 60 minpa, the wound inflicted by the amputation is closed. <b>E–H</b> Sequential images of a representative <i>in vivo</i> 55 min time-lapse movie of a 2 dpf <i>actb1:myl12.1-eGFP</i> transgenic larva. <b>E</b> At 5minpa, there is accumulation of myosin at the leading edge cells. <b>F</b> By 8 minpa the myosin cable is assembled (arrow) and there is tissue contraction - note displacement of arrowheads in comparison with E. <b>G</b> At 30 minpa, the tissue has fully contracted. <b>H</b> At 60 minpa, the wound inflicted by the amputation is closed. <b>I–L</b> Sequential images of a representative <i>in vivo</i> 55 min time-lapse movie of a 2 dpf <i>ctnna-Citrine</i> transgenic larva at different time-points after amputation. <b>I</b> At 5minpa, there is accumulation of alpha-catenin at the leading edge cells. <b>J</b> By 8 minpa this accumulation appears to localize to the actomyosin cable (arrow) and there is tissue contraction - note displacement of arrowheads in comparison with I. <b>K</b> At 30 minpa, the tissue has fully contracted and alpha-catenin is still localized at the wound edge. <b>L</b> At 60 minpa, the wound inflicted by the amputation is closed. Anterior is on the left and scale bars correspond to 50 µm in all images; n = 5 larvae per condition.