Id |
Subject |
Object |
Predicate |
Lexical cue |
T1 |
80-136 |
DRI_Background |
denotes |
Many animals show left-right (LR) asymmetric morphology. |
T2 |
137-252 |
DRI_Background |
denotes |
The mechanisms of LR asymmetric development are evolutionarily divergent, and they remain elusive in invertebrates. |
T3 |
253-354 |
DRI_Background |
denotes |
Various organs in Drosophila melanogaster show stereotypic LR asymmetry, including the embryonic gut. |
T4 |
355-458 |
DRI_Approach |
denotes |
The Drosophila embryonic hindgut twists 90° left-handedly, thereby generating directional LR asymmetry. |
T5 |
459-597 |
DRI_Background |
denotes |
We recently revealed that the hindgut epithelial cell is chiral in shape and other properties; this is termed planar cell chirality (PCC). |
T6 |
598-694 |
DRI_Approach |
denotes |
We previously showed by computer modeling that PCC is sufficient to induce the hindgut rotation. |
T7 |
695-804 |
DRI_Outcome |
denotes |
In addition, both the PCC and the direction of hindgut twisting are reversed in Myosin31DF (Myo31DF) mutants. |
T8 |
805-947 |
DRI_Background |
denotes |
Myo31DF encodes Drosophila MyosinID, an actin-based motor protein, whose molecular functions in LR asymmetric development are largely unknown. |
T9 |
948-1146 |
DRI_Outcome |
denotes |
Here, to understand how PCC directs the asymmetric cell-shape, we analyzed PCC in genetic mosaics composed of cells homozygous for mutant Myo31DF, some of which also overexpressed wild-type Myo31DF. |
T10 |
1147-1320 |
DRI_Background |
denotes |
Wild-type cell-shape chirality only formed in the Myo31DF-overexpressing cells, suggesting that cell-shape chirality was established in each cell and reflects intrinsic PCC. |
T11 |
1321-1499 |
DRI_Background |
denotes |
A computer model recapitulating the development of this genetic mosaic suggested that mechanical interactions between cells are required for the cell-shape behavior seen in vivo. |
T12 |
1500-1732 |
DRI_Outcome |
denotes |
Our mosaic analysis also suggested that during hindgut rotation in vivo, wild-type Myo31DF suppresses the elongation of cell boundaries, supporting the idea that cell-shape chirality is an intrinsic property determined in each cell. |
T13 |
1733-2079 |
DRI_Background |
denotes |
However, the amount and distribution of F-actin and Myosin II, which are known to help generate the contraction force on cell boundaries, did not show differences between Myo31DF mutant cells and wild-type cells, suggesting that the static amount and distribution of these proteins are not involved in the suppression of cell-boundary elongation. |
T14 |
2080-2286 |
DRI_Outcome |
denotes |
Taken together, our results suggest that cell-shape chirality is intrinsically formed in each cell, and that mechanical force from intercellular interactions contributes to its formation and/or maintenance. |