Article

Cell Lineage Reconstruction of Early Zebrafish Embryos Using Label-Free Nonlinear Microscopy

Laboratory for Optics and Biosciences, Ecole Polytechnique, CNRS, INSERM, Palaiseau, France.
Science (Impact Factor: 31.48). 08/2010; 329(5994):967-71. DOI: 10.1126/science.1189428
Source: PubMed

ABSTRACT Quantifying cell behaviors in animal early embryogenesis remains a challenging issue requiring in toto imaging and automated
image analysis. We designed a framework for imaging and reconstructing unstained whole zebrafish embryos for their first 10
cell division cycles and report measurements along the cell lineage with micrometer spatial resolution and minute temporal
accuracy. Point-scanning multiphoton excitation optimized to preferentially probe the innermost regions of the embryo provided
intrinsic signals highlighting all mitotic spindles and cell boundaries. Automated image analysis revealed the phenomenology
of cell proliferation. Blastomeres continuously drift out of synchrony. After the 32-cell stage, the cell cycle lengthens
according to cell radial position, leading to apparent division waves. Progressive amplification of this process is the rule,
contrasting with classical descriptions of abrupt changes in the system dynamics.

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