image: Epithelial cells take a left-right asymmetric shape before the rotation of the gut. To understand the mechanism of left-handed rotation of the fly gut, the team analyzed the shape of cells at the inner side of the gut tube. Along the middle line of the tube, they defined the anterior-posterior axis (upper, left). They measured the angle between the anterior-posterior axis and each cell boundary, and designated it as angle x (shown in white, upper left). Results are shown in the frequency (%) histogram (lower). In this histogram, anterior-posterior axis corresponds to 0 degree, and left-right axis corresponds to -90 or 90 degrees. The frequencies of cell boundaries with the angle X divided into 15 degree range intervals are shown. Before the left-handed rotation, cell boundaries with angle X range from -90 to 0 degrees (shown in orange) appear more often than those from 0 to 90 degrees (shown in blue, left). Thus, the cell shape is left-right asymmetric. On the other hand, after rotation, the left-right asymmetry of the cell shape is diminished, and these cells take a symmetric hexagonal shape. This image relates to an article that appeared in the July 15, 2011, issue of Science, published by AAAS. The study, by K. Taniguchi of Tokyo University of Science in Noda, Japan, and colleagues was titled, "Chirality in Planar Cell Shape Contributes to Left-Right Asymmetric Epithelial Morphogenesis." view more
Credit: Image © <i>Science/</i>AAAS