Type of signaling in which a cytokine acts on the cell that...

The type of cell signaling in which a signal is secreted into the extracellular environment and acts locally on neighboring cells up to a few cell diameters away is called paracrine signaling. In contrast, endocrine signaling involves sending the signal, which in this case is called a hormone, to the entire body. An important class of signaling molecules called steroid hormones bind to the receptor proteins that translocate into the nucleus upon activation. A common regulatory mechanism in cell signaling is the addition of a phosphate to a target protein, which is carried out by enzymes called kinases. G proteins are activated when they bind a molecule of GTP. During G protein-coupled receptor signaling, one of the key activated proteins is the enzyme adenylyl cyclase, which makes cyclic AMP from ATP. A common mechanism of GPCR inactivation is internalization of the receptor from the cell surface. During the process, the receptor is incorporated into the endosome.

Dominador T.