Biology Chapter 11 - Cell Signaling

Hormone

chemicals used in long-distance signaling

growth factors

Regulatory proteins that ensure that the events of cell division occur in the proper sequence and at the correct rate.

paracrine signaling

secreted molecules diffuse locally and trigger a response in neighboring cells

synaptic signaling

a nerve cell releases neurotransmitter molecules into a synapse, stimulating the target cell

endocrine signaling

A type of long-distance signaling in animals that utilizes hormones.

long distance signaling

signaling between cells separated by some distance

reception

The target cell's detection of a signal molecule coming from outside the cell

transduction

conversion of the signal to a form that can bring about a specific cellular response

response

when the transduction signal finally triggers a specific cellular response

signal transduction pathway

a sequence of changes in a series of different molecules

ligand

A molecule that specifically binds to another molecule, often a larger one.

G protein-coupled receptors (GPCRs)

a cell-surface transmembrane receptor that works with the help of a G protein

G protein

a protein that binds the energy-rich molecule GTP

ligand-gated ion channel

Type of membrane receptor that has a region that can act as a "gate" when the receptor changes shape

transcription factors

control which genes are turned on in a particular cell at a particular time

protein kinase

An enzyme that transfers phosphate groups from ATP to a protein ("turns on" proteins)

phosphorylation cascade

A series of enzyme-catalyzed phosphorylation reactions commonly used in signal transduction pathways to amplify and convey a signal inward from the plasma membrane

protein phosphatases

Enzymes that can rapidly remove phosphate groups from proteins.

second messengers

Small, non-protein water soluble molecules or ions involved in many signaling pathways

cyclic AMP

A second messenger derived from ATP and triggers protein kinase A (activated by adenylyl cyclase)

adenylyl cylase

an enzyme embedded in the plasma membrane that converts ATP to cAMP in response to an extracellular signal (activated by protein thats activated by ligand)

inositol triphosphate (IP3)

Second messenger produced by cleavage of a certain kind of phospholipid in the plasma membrane; Stimulates release of calcium from the ER

diacylglycerol (DAG)

A second messenger produced by the cleavage of a certain kind of phospholipid in the plasma membrane

Apoptosis

programmed cell death