Chirality and Left-Right Asymmetry in Developmental Biology

Chirality, the property of an object or system that prevents it from being superimposed on its mirror image, emerges across scales in biology—from molecular assemblies to whole organs. In developing embryos, the establishment of a left–right axis underlies the asymmetric positioning and morphogenesis of organs such as the heart, gut and vasculature. At the heart of this process lies the cytoskeleton, whose actin filaments and associated motors generate intrinsic torque and directional flows that break symmetry at the single-cell level. Genetic determinants, including formins and other actin regulators, set handedness early in cleavage stages, while collective cell behaviours such as intercalation and cortical sliding amplify these biases to shape rotating epithelia and twisted organ tubes. Aberrant asymmetry underpins congenital disorders of laterality, whereas harnessing cell chirality offers routes to engineer helical tissues in vitro. Integrating biophysical, genetic and tissue-scale perspectives has thus become essential for understanding and manipulating asymmetry in development and disease.

Research from Nature Portfolio

Recent studies have revealed how specific actin assembly regulators govern cell-intrinsic chirality and its propagation to multicellular contexts. In controlled micropatterns, depletion or overexpression of formin and profilin isoforms was shown to invert the handedness of actin networks, linking single-cell torque generation to collective alignment in confined cultures. In epithelia of Drosophila, left–right-biased junction remodelling driven by polarized myosin II distribution was found sufficient to produce coherent tissue rotation, establishing a model of asymmetric cell intercalation. Genetic mapping in a pond snail pinpointed a mutation in a tandemly duplicated diaphanous gene as the primary determinant of shell-coiling direction, demonstrating that early asymmetries in gene expression precede and instruct morphological handedness.

Chirality and Left-Right Asymmetry in Developmental Biology publication trend

The graph below shows the total number of articles in chirality and left-right asymmetry in developmental biology across all publications each year (not limited to Nature Index journals).

Technical terms

Chirality: A geometric property whereby a structure cannot be superimposed on its mirror image, critical for molecular and cellular handedness.

Left–Right Asymmetry: The consistent bias along the left–right axis during embryogenesis that positions and shapes organs in a directional manner.

Actin Cytoskeleton: A dynamic network of filamentous actin and associated proteins that generates force and polarity within cells.

Formin: A class of actin-nucleating proteins that control filament polymerisation and influence cellular chirality.

Actomyosin Cortex: The layer of actin filaments and myosin motors beneath the plasma membrane that produces contractile forces and torque.

Cell Intercalation: The process by which cells rearrange within a tissue plane, often in an asymmetric fashion, to drive morphogenetic movements.

References

1. Actin polymerisation and crosslinking drive left-right asymmetry in single cell and cell collectives. Nature Communications (2023).
2. Helical vasculogenesis driven by cell chirality. Science Advances (2024).
3. Active torque generation by the actomyosin cell cortex drives left–right symmetry breaking. eLife (2014).
4. Left–right asymmetric cell intercalation drives directional collective cell movement in epithelial morphogenesis. Nature Communications (2015).
5. Diaphanous gene mutation affects spiral cleavage and chirality in snails. Scientific Reports (2016).