Neuronal Specification Flashcards
What are important steps in cell specification/determination?
- development of neural progenitor cells/neuroblasts
- Production of neuronal and glial progenitor/precursor cells through asymmetric cell division of neuroblasts
- Differentiation of neurons and glial cells from neuronal and glial progenitor/precursor, respectively
How to study cell lineages?
- fluorescent marker molecules
- green fluorescent proteins (GFP)
- C. elegans model
What happens in Drosophila neurogenesis?
- neuroectoderm moves to ventral side of embryo during gastrulation
- 60 proneural clusters form
- one cell per cluster develops into a neuroblast
- neuroblast divides into a neuroblast and ganglion mother cell
- ganglion mother cell become neuronal and glial progenitor cells
What happens during Drosophila transformation?
neuroectoderm becomes neuroblast
What happens during symmetric cell division?
cell divides to make two of itself
What happens during asymmetric cell division?
a cell divides in a way that it makes a clone of itself but also makes differentiated cell
What happens during vertebrate neurogenesis?
- neuroectoderm undergoes transformation into a neuroblast
- neuroblasts multiply through symmetric cell division
3a. neuroblasts become neuronal progenitor cell
3b. neuroblasts become glial progenitor cell
imbalance of delta notch signaling results in what?
lateral inhibition
what are proneural gene products? what do they do?
achaete-scrute protein activates delta expression
What does delta activate?
activates notch signaling in neighboring cells and less achaete-scute
What do cells with high level of notch signaling become?
epidermal
What do cells with high levels of delta and achaete-scute become?
neuroblasts
What is the proneural gene in vertebrates?
neurogenin which also promotes neuroblast determination
What do cell polarity factors do?
determine apical side of the neuralblast
What are cytoplasmic determinants?
factors localized to the basal side of the cell
