Cell Signaling

cellular response

A(n) ________ to the environment can be critical for survival.

Phospholipase C

________ cleaves plasma membrane phospholipid PIP₂ producing diacylglycerol (DAG) and inositol triphosphate (IP3)

Α subunit

________ activates phospholipase c.

Contact dependent

________ signaling: Molecules bound to the surface of cells serve as signals to.

Ca2+

________ exerts a variety of effects on cell behavior.

Receptors

________ are comprised of extracellular and intracellular domains.

Direct intercellular signaling

________: Cell junctions allow signaling molecules to pass from one cell.

Signal transduction

________: activated receptor stimulates a sequence of changes.

Second messengers

________: relay signals inside cells.

messenger

First ________: signals binding to the cell surface.

Α subunit

________ binds to adenylyl cyclase enzyme**,** stimulating synthesis of cAMP.

Example

Glucose signals yeast cells to increase glucose transporters and enzymes allowing efficient uptake and use of glucose

Direct intercellular signaling

  Cell junctions allow signaling molecules to pass from one cell

Contact-dependent signaling

  Molecules bound to the surface of cells serve as signals to

Autocrine signaling

  Cells secrete signaling molecules that bind to their own cell surface or similar neighboring cells

Paracrine signaling

signal does not affect originating cell, but does influence nearby cells

Endocrine signaling

signals called hormones travel long distances and are usually longer lasting in effect

Receptor activation

signaling molecule binds to receptor

Signal transduction

activated receptor stimulates a sequence of changes

First messenger

signals binding to the cell surface

Second messengers

relay signals inside cells

Signal amplification

binding of signal to one receptor can cause the synthesis of many cAMP molecules that activate PKA, and each PKA can phosphorylate many proteins

Speed

in one experiment a substantial amount of cAMP was made within 20 seconds after addition of signal