Membrane proteins are among the most important proteins biologically because they allow cells to communicate with their environm
ents. In humans, they determine whether the immune system recognizes the cell as foreign or not and they are the targets of most pharmaceuticals. In all organisms, membrane proteins are responsible for other functions as well. One function determines when and if cell division takes place. That is
One function determines when and if cell division takes place. That is activation of growth hormones. When these hormones start forming, that is when the cell is going to be divided.
Modulation of Ca+2 channel Epinephrine also causes an increase in cAMP that stimulates PKA that is protein kinase A, which in turn phosphorylates the voltage-gated Ca+2 channel that is the L channel. This phosphorylation results in a protein conformational change that enchances the channels activity.
