Chapter 15
4D Live Imaging and Analysis of Chick Embryo Somites
Gi Fay Mok, James McColl, and Andrea Mu ¨ nsterberg
Abstract
Avian (chick) embryos are an established and accessible model organism making them ideal for studying
developmental processes. Chick embryos can be harvested from the egg and cultured allowing real-time
observations and imaging. Here, we describe ex vivo culture and preparation of somite tissue followed by
time-lapse multi-photon microscopy, image capture and processing. We applied this approach to perform
live imaging of somites, the paired segments in vertebrate embryos that form in a regular sequence on either
side of the neural tube, posteriorly from presomitic mesoderm (psm). Somites give rise to cell lineages of the
musculoskeletal system in the trunk such as skeletal muscle, cartilage and tendon, as well as endothelial cells.
Until recently it was not possible to observe the cellular dynamics underlying morphological transitions in
live tissue, including in somites which undergo epithelial-to-mesenchymal transitions (EMT) during their
differentiation. In addition to the experimental setup, we describe the analytical tools used for image
processing.
Key words Live imaging, Somites, Chick embryo, Multi-photon microscopy, Image processing
1 Introduction
The chick embryo is a classic vertebrate model for studying developmental processes in amniote species [1]. Embryos are easily
accessible as they develop outside the mother and this enables
in vivo manipulation experiments. They can be removed from the
egg and cultured for a few days or, as described in this chapter,
tissue slices can be dissected and cultured for live imaging [2].
Recent advances in genetic modification and new transgenic lines
with fluorescently labeled cells will further improve cell imaging
approaches [3]. Embryo morphogenesis is complex, and a better
understanding of the underlying processes is of fundamental
importance. Morphogenesis is closely linked to and driven by cellular dynamics such as proliferation, cell growth, cell movement,
and also cell migration, which often occur rapidly over short timescales. However, it has been surprisingly challenging, to date, to
image, capture, and analyze these processes in live tissues.
Kyra Campbell and Eric Theveneau (eds.), The Epithelial-to Mesenchymal Transition: Methods and Protocols,
Methods in Molecular Biology, vol. 2179, https://doi.org/10.1007/978-1-0716-0779-4_15,
© Springer Science+Business Media, LLC, part of Springer Nature 2021
173
4D Live Imaging and Analysis of Chick Embryo Somites
Gi Fay Mok, James McColl, and Andrea Mu ¨ nsterberg
Abstract
Avian (chick) embryos are an established and accessible model organism making them ideal for studying
developmental processes. Chick embryos can be harvested from the egg and cultured allowing real-time
observations and imaging. Here, we describe ex vivo culture and preparation of somite tissue followed by
time-lapse multi-photon microscopy, image capture and processing. We applied this approach to perform
live imaging of somites, the paired segments in vertebrate embryos that form in a regular sequence on either
side of the neural tube, posteriorly from presomitic mesoderm (psm). Somites give rise to cell lineages of the
musculoskeletal system in the trunk such as skeletal muscle, cartilage and tendon, as well as endothelial cells.
Until recently it was not possible to observe the cellular dynamics underlying morphological transitions in
live tissue, including in somites which undergo epithelial-to-mesenchymal transitions (EMT) during their
differentiation. In addition to the experimental setup, we describe the analytical tools used for image
processing.
Key words Live imaging, Somites, Chick embryo, Multi-photon microscopy, Image processing
1 Introduction
The chick embryo is a classic vertebrate model for studying developmental processes in amniote species [1]. Embryos are easily
accessible as they develop outside the mother and this enables
in vivo manipulation experiments. They can be removed from the
egg and cultured for a few days or, as described in this chapter,
tissue slices can be dissected and cultured for live imaging [2].
Recent advances in genetic modification and new transgenic lines
with fluorescently labeled cells will further improve cell imaging
approaches [3]. Embryo morphogenesis is complex, and a better
understanding of the underlying processes is of fundamental
importance. Morphogenesis is closely linked to and driven by cellular dynamics such as proliferation, cell growth, cell movement,
and also cell migration, which often occur rapidly over short timescales. However, it has been surprisingly challenging, to date, to
image, capture, and analyze these processes in live tissues.
Kyra Campbell and Eric Theveneau (eds.), The Epithelial-to Mesenchymal Transition: Methods and Protocols,
Methods in Molecular Biology, vol. 2179, https://doi.org/10.1007/978-1-0716-0779-4_15,
© Springer Science+Business Media, LLC, part of Springer Nature 2021
173