Laboratories and faculty

Developmental Biomedical Science

Assoc Prof. Sasai
Associate Professor
SASAI Noriaki
Assistant Professor
Labs HP

Outline of Research and Education

The central nervous system, a critical organ for controlling individuals’ body conditions, is comprised of a variety types of neurons, and its generation undergoes a number of regulatory steps mainly at the embryonic stages. We intend to elucidate the molecular mechanisms leading to this complexity by employing chick and mouse embryos, and mouse embryonic stem (ES) cells as experimental systems.

We are also interested in the homeostasis of functional neurons. By using model mice which develop particular inherited retinal diseases, we envisage proposing novel therapeutics for these related dystrophies.

Overall, our research program aims to be influential in cell and developmental biology and will furthermore be both scientifically and technically cross-disciplinary spanning basic biology and biomedical sciences.

Major Research Topics

Mechanisms leading to pattern formation and size control of the developing central nervous system

The neural tube is the embryonic tissue of the central nervous system where a number of functional neurons are produced and distributed in a quantitatively and positionally precise manner. This accuracy is mainly achieved by extracellular molecules including BMP, Wnt and Sonic Hedgehog (Shh). These molecules form gradients within the tissue and induce different types of neurons. In addition to the fate assignments, these signal molecules control proliferation of the cells. We are particularly interested in the relationship between cell fate determination and the proliferation of the cells.

Homeostasis of postnatal cells

How functional cells are maintained is also an important question. We possess genetically mutated mice that model retinal degeneration. While these mutant mice develop to normal retinal structure, the retina start to degenerate once their eyes open soon after birth. We are seeking the primary mechanisms leading to this retinal degeneration by using high-throughput sequence analysis and try to develop novel therapeutic methods.

In addition, our recent study has suggested that the retinal degeneration coincides with many more dystrophies in other organs. We are therefore aiming to propose further therapeutic methods through systemic analysis of these model mice.

Fig. 1
Fig. 1 A chick embryo incubated for 4 days.
Fig. 2
Fig. 2 Dopaminergic neurons cultured in vitro.
Fig. 3
Fig. 3 Eye phenotype in Prominin-1 (Prom1) deficient mice. The outer segments are degenerated (A, B), and Rhodopsin proteins are misplaced in the photoreceptor cells of the Prom1-knockout eyes (C, D).


  1. Yatsuzuka et al., Development, 2019
  2. Kadoya and Sasai, Frontiers in Neurosci., 2019
  3. Kutejova et al., Dev Cell, 36, 639-653, 2016
  4. Luehders et al., Development, 142, 3351-3361, 2015
  5. Dellett et al., Investigative Ophthalmology and Visual Science, 56, 164-176, 2015
  6. Sasai et al., PLOS Biology, 12, e1001907, 2014