Epithelial Cell Chirality Revealed by Three-Dimensional Spontaneous Rotation

Abstract

Our understanding of the left-right (LR) asymmetry of embryonic development, in particular the contribution of intrinsic handedness of the cell or cell chirality, is limited due to the confounding systematic and environmental factors during morphogenesis and a ack of physiologically relevant in vitro 3D platforms. Here we report an efficient two-layered biomaterial platform for determining the chirality of individual cells, cell aggregates, and self-organized hollow epithelial spheroids. This bioengineered niche provides a uniform defined axis allowing for cells to rotate spontaneously with a directional bias toward either clockwise or counterclockwise directions. Mechanistic studies reveal an actin-dependent, cell-intrinsic property of 3D chirality that can be mediated by actin cross-linking via α-actinin-1. Our findings suggest that the gradient of extracellular matrix is an important biophysicochemical cue influencing cell polarity and chirality. Engineered biomaterial systems can serve as an effective platform for studying developmental asymmetry and screening for environmental factors causing birth defects.cell chirality | left-right asymmetry | cell polarity | tissue morphogenesis | biomaterial A lmost all vertebrates have an asymmetric body plan, a deviation from which often leads to severe malformations (1, 2). In recent years, increasing evidence has suggested that embryonic and organ-specific left-right (LR) asymmetries, such as hindgut and genitalia rotation in Drosophila and symmetry breaking in pond snails (3-6), can arise from the LR bias at a cellular level, also termed cell chirality (7,8). In addition, this cellular asymmetry has been demonstrated in various models, including early asymmetry in Caenorhabditis elegans (9, 10), the chiral properties of Xenopus egg cortex (11, 12), asymmetric distribution of chirality related proteins at the early developmental stages of different animals (13), and migratory biases of cultured cells in vitro (12, 14-17). However, cell chirality is poorly understood in developing embryos, despite its scientific and clinical significance, due to complexities in imaging and molecular assays when dealing with animal models and confounding systematic and environmental factors that influence data explanation and hinder mechanistic findings. Therefore, it is of great importance to establish a biomimetic system for LR symmetry breaking that truly recapitulates 3D multicellular chiral morphogenesis.Cell chirality is a fundamental property of the cell, and the universality was not widely regarded until the recent use of microfabricated 2D in vitro systems (16,(18)(19)(20), including the 2D microcontact printing developed by us. In these systems, the cells were confined in a narrow area that allows the cells to exhibit their chiral biases in various formats, including cytoskeleton dynamics, cell migration, and multicellular biased alignment. With these new tools, cell chirality was found to be phenotype-dependent and related to the cross-linking of formin-associated actin bund...

Effect of static magnetic field on DNA synthesis: The interplay between DNA chirality and magnetic field left‐right asymmetry

“…16,17 Chirality can also be observed as the directional rotation of cellular organelles, cytoskeleton, and cells as a whole. 18 Findings [19][20][21][22][23] suggest that chirality is a fundamental property of the cell that depends on the chiral nature of the mitotic spindle and cytoskeleton network, such as actin and microtubule bundles. It is believed that all amino acids are present in all proteins only in the left configuration.…”

Early Committed Clockwise Cell Chirality Upregulates Adipogenic Differentiation of Mesenchymal Stem Cells

“…Cell chirality is an intrinsic, left‐right (LR)‐biased cell mechanics driven by intracellular molecular handedness. [ 1–4 ] Examples were found such as active torsion of cells [ 1,5,6 ] and chiral skew event that establishes an uneven distribution of cells in Caenorhabditis elegans embryos. [ 7 ] It is believed that cell chirality can ultimately determine the LR asymmetry in morphogenesis.…”

Making and breaking symmetry in development, growth and disease

“…For example, the dextral looping of the zebrafish heart is controlled by a heart-intrinsic cytoskeletondependent mechanism (Desgrange et al, 2018;Noël et al, 2013). Thus, asymmetric information is transferred from smaller to larger scales multiple times independently within the same embryo (Chin et al, 2018;Ray et al, 2018), rather than emerging in a single symmetry-breaking event.…”