BIOL 303 Lecture Notes - Lecture 11: Notch Signaling Pathway, Positive Feedback, Growth Factor
14 May 2018
School
Department
Course
Professor
Biol 303 Jan 23rd
General
• The class is moving starting Thursday January 25th to Otto Maass 10
Finish from last week – Anchor cell slide
• Anchor cell releases a growth factor (LIN-3)
• An RTK (LET-23) biases the outcome
• NOTCH signal pathway is the result
Vuva development
• Specification of the anchor cell (AC)
• We only want there to be one anchor cell
• There are cells in the gonad that could become anchor cell or VU cell (ventral uterine)
• Experiment shows that both cells (Z1.ppp and Z4.ppp) are equally capable of becoming
the anchor cell and if you knock one out early on, the other one will become the anchor
cell
• LIN-12 signalling is required for VU fate
• The anchor faze is not associated with having the LIN-12 receptor
Its a attle!
• Two cells that are trying the same amount, but random processes will allow one to win
and determine what type the cell becomes
• LIN-12 and LAG-2 are battling to try and make the cell a VU cell (LIN-12) or an anchor
cell (LAG-2)
• Positive feedback mechanisms enforce the change one way or another once one fate is
favored even a little
• The two cells with undetermined fates are interacting and when once starts to turn, the
other turns into the opposite
Cis/trans interaction between Notch and its ligands
• Review this :p
Two kinds of interaction between notch and delta
• F
Lateral inhibition
• This inhibition works in a pattern → if one cell turns (blue), it will make the cell two cells
over turn, not the one right next to it
• The cells that do not get turned become the opposite (white)/ remain epithelial cells
Lol More worm stuff
• Epistasis experiments
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
General: the class is moving starting thursday january 25th to otto maass 10. Finish from last week anchor cell slide: anchor cell releases a growth factor (lin-3, an rtk (let-23) biases the outcome, notch signal pathway is the result. Cis/trans interaction between notch and its ligands: review this :p. Two kinds of interaction between notch and delta: f. Lol more worm stuff: epistasis experiments, can help us determine which order genes/proteins are in, we learn which genes/proteins are downstream or upstream of others. Types of pathways: substrate dependent pathway: you have a series of genes that could be catalyzing the production of some compound, cells differentiating over time, but for each step to occur you need the previous step to occur. Each step is contingent on the outcome of the previous step: switch regulation pathway: biochemical pathways with proteins/ligands turning each other on and off.
