Cell Bio Lecture 19 (Chap 16)

Vocabulary flashcards covering cell signaling concepts.

Hormones

Signaling molecules that travel a long distance to reach their target cells.

Local Mediators

Signaling molecules that act locally to regulate inflammation or wound repair.

Neurotransmitters

Signaling molecules that transmit signals from cell to cell, such as neurotransmitters.

Contact-dependent Signaling

A type of cell signaling that requires direct contact between cells, such as the Delta-Notch interaction.

Adrenaline (epinephrine)

Increases blood pressure, heart rate, and metabolism; produced by the adrenal gland

Cortisol

Affects metabolism of proteins, carbohydrates and lipids in most tissues; produced by the adrenal gland.

Estradiol

Induces and maintains secondary female sexual characteristics; produced by the ovary.

Glucagon

Stimulates glucose synthesis, glycogen breakdown, and lipid breakdown, e.g., in liver and fat cells; produced by alpha cells of pancreas

Insulin

Stimulates glucose uptake, protein synthesis and lipid synthesis, e.g., in liver cells; produced by beta cells of pancreas.

Testosterone

Induces and maintains secondary male sexual characteristics; produced by the testes.

Thyroid hormone (thyroxine)

Stimulates metabolism of many cell types; produced by the thyroid gland.

Epidermal growth factor (EGF)

Stimulates epidermal and many other cell types to proliferate; produced by various cells.

Platelet-derived growth factor (PDGF)

Stimulates many cell types to proliferate; produced by various cells, including blood platelets.

Nerve growth factor (NGF)

Promotes survival of certain classes of neurons and promotes growth of their axons; produced by various innervated tissues.

Transforming growth factor-B (TGF-B)

Inhibits cell proliferation; stimulates extracellular matrix production; produced by many cell types.

Histamine

Causes blood vessels to dilate and become leaky, helping to cause inflammation; produced by mast cells

Nitric Oxide (NO)

Causes smooth muscle cells to relax; regulates nerve cell activity; produced by nerve cells and endothelial cells lining blood vessels.

Acetylcholine

Excitatory neurotransmitter at many nerve-muscle synapses and in the central nervous system; produced by nerve terminals

y-Aminobutyric acid (GABA)

Inhibitory neurotransmitter in central nervous system; produced by nerve terminals.

Delta

Membrane-bound signal protein that inhibits neighboring cells from becoming specialized in the same way as the signaling cell; produced by prospective neurons and various other developing cell types.

Intracellular Signaling Pathway

A signaling pathway where an extracellular signal molecule binds to a cell-surface receptor, leading to altered protein function or altered protein synthesis.

Cell-Surface Receptors

Receptors located on the cell surface that bind to hydrophilic signaling molecules.

Intracellular Receptors

Receptors located inside the cell that bind to small hydrophobic signaling molecules.

Steroid Hormones

A class of signaling molecules, like cortisol and estradiol, that utilize intracellular receptors.

Guanylyl Cyclase

An enzyme that catalyzes the production of cyclic GMP (cGMP) in response to nitric oxide (NO).

Small Messenger Molecules

Small intracellular molecules that diffuse to act on intracellular signaling proteins.

Molecular Switches

Proteins that act as switches, turned on or off by phosphorylation or GTP-binding.

Signaling by Protein Phosphorylation

A type of molecular switch activated by protein phosphorylation, utilizing serine/threonine kinases and tyrosine kinases.

Signaling by GTP-Binding Protein

A type of molecular switch activated by GTP binding and inactivated by GTP hydrolysis.

Ion-Channel-Coupled Receptors

Receptors that open or close in response to a signal molecule binding.

Enzyme-Coupled Receptors

Receptors where the signal molecule activates an enzymatic domain or an associated enzyme.

G-Protein-Coupled Receptors

Receptors that activate G proteins upon binding a signal molecule.

GPCRs

The largest family of cell surface receptors, targeted for drug development.

G Proteins

Proteins with three subunits (alpha, beta, and gamma) that are activated by GPCRs.

Receptor Tyrosine Kinases (RTKs)

Kinases for which the human genome encodes 59, including the receptors for insulin and many growth factors.

FOXO

In Absence of growth factor, transcription of FOXO-induced genes (genes that inhibit cell proliferation)

MAP Kinase Cascade

A signaling cascade that is abundant and conserved; if Ras is always active, then cells grow too much.