Development of sense organs Flashcards
What is the touch cell lineage for C.elegans
Q cell differentiates into a Q1.a and a Q1.p cell
UNC-86 turned on in Q1.p to produce an interneuron and a GBT cell (touch cell) - mutant UNC-86 leads to a loss of the touch cell
In drosophila what are all sensory structures derived from
SOPs - sensory neuron precursors
What role does Notch play in the lineage a cell adopts
Where Notch is inhibited initially, will later form a neuron
What protein is asymmetrically distributed between 2 cells and what affect does it have on Notch
Numb - inhibits notch ultimately leading to that cell acquiring a neural fate
What is the repeating unit that makes up the drosophila eye
Omatidia - around 800
How many photoreceptors are there in a single Omatidia
8
What is the morphogenetic furrow and what role does it play in the drosophila eye
A wave of differentiation that moves anteriorly across the developing retina - Hh is secreted posterior to the furrow by the maturing photoreceptors
In response to Hh a TF called atonal is upregulated. The first cell to produce atonal becomes rhabdomere 8
What do R8 cells signal to adjacent cells
Set of TF tell adjacent cells to change their fate - Notch and Delta signalling produces spaced R8 cells
How does an R8 cell cause an R7 cell to become a photoreceptor and not a cone cell
Through the action of the TF bride of sevenless
Development is dependent on a variety of localised signals
How do the placodal origins of the ear, lense, olfactory epithelium of vertebrates similar to sensory neurons e.g. DRG
Both are neural crest derived - Neural crest border cells in the most anterior region of the embryo are crucial for head placode development
