Flashcards in Molecular and Genetic Basis of Tooth Development Deck (65)
Neural Crest cells
Stem cells that migrate through defined paths to reach the branchial arches
Where are neural crest cells formed?
At the back of the neural tube
When doe neural crest cells migrate?
When the neural tube closes at week 4
What are the types of division that stem cells undergo?
Stem cells divide into 2 identical stem cells
Can divide into 1 differentiated cell, and 1 identical stem cell
What does it mean for Neural crest cells to be Multipotent stem cells? Why is it important?
Can interact with other cell layers
Embryonic development of the branchial arch structures relies on complicated but precise tissue-tissue interaction
Regulates NCC cells during morphogenesis
Controls the position, size, and shape of organs
Provides environment for NCC cells to populate
Develops pharyngeal pouch-generated organs
(thyroid, parathyroid, and thymus)
Segments of NCC on the neural crest
Where do r1-2 migrate?
Branchial arch I
Where does r4 migrate?
Branchial arch II
Where do r6-7 migrate?
Branchial arch III
What rhombomeres make up the Trigeminal nerve?
What rhombomeres make up the facial nerve?
What rhombomeres make up the glossopharyngeal nerve?
What segments do nerves exit from to innervate peripheral target structures?
Even segments (but they collect from all segments)
A group of homeobox genes, which possess a unique homeobox (DNA sequence), which encodes a conservative homeodomain (protein segment)
What is the protein product if a Hox gene is expressed?
A transcription factor, which controls other gene expression
Which NCCs are Hox free?
The ones that migrate to the first branchial arch (r1 and 2)
Hox genes are carried, but just not expressed
Which NCCs express Hox?
Ones that migrate to teh second branchial arch and further
Family of homeobox genes that produce differences between the maxilla and the mandible
Required for the development of the proximal portion of the first branchial arch (maxillary process)
Required for the development of the distal portion of the first branchial arch (mandibular process
D1x1/2 double mutants
Causes a lack of all maxillary molars - mandible is unaffected
D1x5/6 double mutants
Lower jaw mirrors the upper jaw
What drives the entire process of tooth development?
Interaction between epithelium and mesenchyme
What does the epithelium become during tooth development?