Neural crest and pigmentation Flashcards
From what tissue (gastrulation) does the neural crest cells originate?
The ectoderm
What does neural-crest cells give rise to?
- The peripheral nervous system (PNS)
- Endocrine and paraendocrine derivatives
- Pigment cells
- Facial cartilage and bones
- Connective tissue
What cell types is especially important in vertebrate evolution?
Neural crest cells
Where does the neural crest originate?
As the neural plate becomes a tube, they are located on top (dorsally), where they undergo the epithelial to mesenchymal transition (MET) and migrate
What signaling is important during the initial migration of neural crest cells?
Wnt and BMP (dosage and timing is important)
What are the four types of neural crest cells?
Cranial, Cardiac, Trunk and vagal and sacral (gut)
What is special about the cranial neural crest cells?
They can create cartilage, muscle, bone and connective tissue
What regulated the steps of neural crest differentation?
Paracrine factors causing changes in gene expression
What is neural crest delamination?
The process in which the cells stop adhering to the epithelial layer, and start migrating. Cadherins are important. Contact may cause inhibition for some cells and collective migration for others
What is the cellular basis of pigmentation in mammals and birds?
Melanocytes synthesize melanin (dark) and pheomelanin (yellow to red).
Melanin is transported to keratinocytes.
What concept underlies color patterns?
The reaction diffusion model (Turing patterns)
