Article

Cellular self-organization by autocatalytic alignment feedback

Department of Aerospace and Mechanical Engineering, University of Arizona, Tucson, AZ 85721 USA.
Journal of Cell Science (Impact Factor: 5.43). 12/2011; 124(Pt 24):4213-20. DOI: 10.1242/jcs.088898
Source: PubMed

ABSTRACT

Myoblasts aggregate, differentiate and fuse to form skeletal muscle during both embryogenesis and tissue regeneration. For proper muscle function, long-range self-organization of myoblasts is required to create organized muscle architecture globally aligned to neighboring tissue. However, how the cells process geometric information over distances considerably longer than individual cells to self-organize into well-ordered, aligned and multinucleated myofibers remains a central question in developmental biology and regenerative medicine. Using plasma lithography micropatterning to create spatial cues for cell guidance, we show a physical mechanism by which orientation information can propagate for a long distance from a geometric boundary to guide development of muscle tissue. This long-range alignment occurs only in differentiating myoblasts, but not in non-fusing myoblasts perturbed by microfluidic disturbances or other non-fusing cell types. Computational cellular automata analysis of the spatiotemporal evolution of the self-organization process reveals that myogenic fusion in conjunction with rotational inertia functions in a self-reinforcing manner to enhance long-range propagation of alignment information. With this autocatalytic alignment feedback, well-ordered alignment of muscle could reinforce existing orientations and help promote proper arrangement with neighboring tissue and overall organization. Such physical self-enhancement might represent a fundamental mechanism for long-range pattern formation during tissue morphogenesis.

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Available from: Michael Junkin, Jan 06, 2016
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    • "However, the structural complexity is limited by the mechanical precision of those approaches. Additionally, cellular self-organization, an essential feature in tissue development that uses mechanisms such as cell migration [14] and cellecell alignment [15], would also defeat and frustrate such artificial attempts, eventually disorganizing the defined morphology. "
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