Cell Polarity Flashcards
What is cell polarity?
The organisation of protein at plasma membrane and inside cells.
What are the 2 routes to generate diversity?
- Intrinsic: polar mother cell divides to generate 2 different daughters.
- Extrinsic: polar mother cell divides into two identical daughters, the daughters change due to environmental signals.
What did Whitman discover in 1878?
There are distinct partitioned cytoplasm domains in leeches.
What did Conklin discover in 1905?
There is 5 types of cytoplasm that is inherited in different cell types in oocytes.
What happens to cell polarity during fertilisation?
Symmetry is broken.
The sperm entry point determines the posterior pole and axis of the cell.
The sperm delivers the microtubule organising centre to the cell.
How is polarity established in the embryo?
Par 1 and 2 genes are on the posterior cortex.
They work antagonistically with Par3 and Par 5 on the anterior cortex.
Microtubules act on the mitotic spindle and drags it to posterior end.
Where was the cell polarity network first discovered?
C. elegans
How is apical basolateral polarity established?
Par genes.
How is glucose transcellularly transported?
Glucose and Na+ enter the cell by a Na+ driven glucose pump.
Glucose exits the cell by a passive carrier protein.
Na+ exits the cell by a Na+ K+ pump.
What contributes to the establishment of polarity?
Vesicular trafficking.
How is polarity in bacteria established?
Plasmids are dragged by ParM filaments
Why is cell polarity lost in tumours?
Invasive and malignant properties. Due to interference of vesicular trafficking
What are the Amotyl family resposible for?
Scaffold proteins.
Binding domains at junctional proteins.
What family is responsible for blood vessel formation?
Amotyl family
What does high levels of Amotyl2 cause?
Par2 in wrong locations of the cell
