Question

Share your thoughts with your peers about how Sonic hedgehog specifies the sclerotome. Include all citations

Answer 1

Sonic hedgehog specifing the sclerotome:

The tissues, acting through the secreted signaling molecule Sonic hedgehog (Shh), appear to be critical for the formation of the sclerotome.Signals from the floor plate and notochord promote chondrogenesis of the somitic mesoderm.Sonic hedgehog is a protein that in humans is encoded by the SHH ("sonic hedgehog") gene. Both the gene and the protein may also be found notated alternatively as "Shh". Sonic hedgehog is one of three proteins in the mammalian signaling pathway family called hedgehog.

• The Shh not only acts in collaboration with BMPs to induce cartilage, but that it changes the competence of target cells to respond to BMPs. In the absence of Shh, BMP administration induces lateral plate gene expression.
• Shh signals are required only transiently for somitic chondrogenesis in vitro, and act to provide a window of competence during which time BMP signals can induce chondrogenic differentiation.
• Sonic hedgehog indeed plays a major role in inducing the formation of the sclerotome ventrally.