How do cells organize themselves into vastly different tissues and organs during development? This is a fundamental question for developmental biologists, and thankfully amazing microscopy can let us see it all unfold (or fold, or zip, or contract, or converge, or invaginate, or…well, you get the point).
Morphogenesis is the physical shaping of an organism during development. Because of the dynamic nature of morphogenesis, it has been helpful for biologists to image these events while they are happening, rather than taking single snapshot images. A recent paper uses live imaging microscopy techniques to look at the fruit fly’s egg chamber, which elongates 1.7-fold during its development. This paper describes how the surface of the egg undergoes oscillations of contractions that are due to oscillations of myosin accumulation. These contractions lead to the elongation of the tissue. Image above shows the periodic pattern of myosin accumulation (red) at different developmental stages of egg chamber development, with cartoons (top) as a guide.
BONUS!! Movie of above image can be seen here. Many more movies from this paper can be found here.
He, L., Wang, X., Tang, H., & Montell, D. (2010). Tissue elongation requires oscillating contractions of a basal actomyosin network Nature Cell Biology, 12 (12), 1133-1142 DOI: 10.1038/ncb2124
Adapted by permission from Macmillan Publishers Ltd, copyright 2011