Molecular Recogniton
Signalling Cascades & Long-Term Responses
Two examples will be discussed in this lecture
Signal coming in and received by the cell and to receive a signal is by a receptor
signal going from outside into the cell.
Signal pipeline into the nucleus
Transcripton in nucleus
So, sequence can be changed
More amplified the signal can be controlled at a
checkpoint
Cytokines- blood cells and immune system
>50 cytokines known
small proteins 5-20 kDa like 150 amino acids in length
released by cells can even stmulate itself
affect other cells
especially important for cells of the immune system
Four distnct structural families: All follow the same principles
•TNF
•IFN
•chemokines
•EPO hematopoeitin
1 EPO molecule and two receptors it is a beta sheet structure for receptor and alpha helix
for protein binding.
can take the receptor and see what’s different in EP types
cytokines share a common structure also among the receptors but the interface between
the receptors is different. Eeptde interacton different.
The cells mature and would change so do this by looking at the cells receptors
Important if you have the right receptor and ligand
Also, dependent on development and cell type
Cells respond differently under development
- Chromatn structure-
- constellaton of the transcripton factors when one set is actve another cell may
have TFs actve as well.