Cell Communication Flashcards
Contact dependent cell communication
Cell to cell. Signal cell binds to target cell, passes a signal molecule. E.g. notch pathway
What is Synaptic cell communication
Neurons. Neurotransmitters diffuse across the synapse.
What is paracrine cell communication?
Signalling cell releases signalling molecule (local mediator) to other target cells. Local mediator interacts with extracellular membrane of target cell and triggers signalling pathway.
What is endocrine cell communication?
Signalling molecule travels in blood stream to target cell. E.g. adrenaline. Target cells express receptors.
What is a Morphogen?
A signalling factor that dictates cell fate.
What are the 3 ways cells respond?
- Altered metabolism
- Altered gene expression
- Altered cell shape
What does a morphogen gradient dictate?
Different cell fates. The Strength of the gradient dictates how a cell reacts.
What does bicoid mRNA gradient in a Drosophila dictate?
Acts as a morphogen, defines anterior parts of embryo.
What is the fastest speed of response?
Changing the structure of an existing protein. E.g. ion channel.
What speed of response is ‘quite fast’?
Changing post translaitional modification (phosphorylation).
What is the slowest speed of response?
Changing protein levels via gene expression.
Myeleoproliferative neoplasms
JAK2 V617F mutation. Blood cancer.
Chronic myeloid leukaemia
Overexpression of Abl. Abl kinase inhibitor used to treat.
Positive feedback.
Production of A produces B, which produces more A. Reaches max and plateaus
What is negative feedback?
Production of A produces B, which produces less A. Reaches max then decreases.
