The sea lamprey is unusual amongst vertebrates for a number of reasons. One of the most surprising features is its elimination of about 20% of its entire genome in most of its embryonic cells. The lab of Jeramiah Smith in the Biology Department is examining this fascinating phenomenon. The loss of chromosomes can be observed in the mitotic figures of somatic cells during early embryogenesis. In the video and in yellow boxes of the single image, chromosomes that are in the process of being eliminated are seen lagging behind the retained chromosomes in some of the dividing cells. Here, early lamprey embryos were collected, fixed, and the DNA stained using Syto21. Stained embryos were cleared in RIMS, embedded in agarose and imaged by LSFM using the Zeiss Lighsheet Z.1. The entire embryo is approximately 1000 microns in diameter.

Image type: Light Sheet Fluorescence Microscopy of optically cleared lamprey embryo

Instrument: Zeiss Lighsheet Z.1, CLARITY sample chamber, 5x objective

Label: Syto21 DNA stain

Processing: Zeiss Zen, Arivis Vision4D, Adobe Photoshop

Microscopists: Vladimir Timoshevskiy and Cody Saraceno