Adding just the right mixture of signaling molecules — proteins involved in development — to human stem cells can coax them to resemble somites, which are groups of cells that give rise to skeletal ...

During somitogenesis, presomitic mesoderm (PSM) can be divided into at least two distinct regions: region I (posterior PSM) and region II (anterior PSM), which correspond to the two distinct cellular ...

Scientists have managed to generate complex embryo-like structures from mouse embryonic stem cells. These structures, called gastruloids, can now for the first time grow somites, the blocks of tissue ...

Vertebrates have a pretty diverse array of body plans, and one of the reasons for this is some evolutionary flexibility in the length of their primary body axis, the one that runs from head to tail.

How are the body’s segments formed? The body of a vertebrate organism consists of segmented axes, which is most distinct in the skeleton. The process of somitogenesis is key to the development of ...

These primitive jawless fish could hold clues to the evolutionary origin of vertebrate heads, as evidenced by detailed embryological analyses. The origin of the vertebrate skull is a topic of much ...

Some of our organs, such as the liver and the heart, are lateralized. As our bodies develop they mostly display bilateral symmetry across the vertebral column. A new molecular pathway, which plays a ...

The spinal column is the central supporting structure of the skeleton in all vertebrates. Not only does it provide a place for muscles to attach, it also protects the spinal cord and nerve roots.

Figure 1: A fluorescence image of an induced presomitic mesoderm (iPSM) tissue model, where cells expressing the Hes7 gene—a key regulator of somite formation—are labeled green. Purple cells express a ...