Cell Membrane Signaling

How do cell communicate with each other?

Cell signaling

What type of signaling enables long-distance cell-to-cell communication?

Endocrine

Where are proteins/peptides stored?

Stored in vesicles

What are proteins/peptides composted of?

Amino acids

What is the composition of steroids?

Cholesterol

What is the composition of amines?

Tyrosine or tryptophan

Where are steroids stored?

they are not

Where are amines stored?

Catecholamines in vesicles, Thyroid weird

Where are protein/peptide receptors?

On cell membrane

Where are steroid receptors?

intracellular thus changing gene expression

Where are amine (catecholamines) receptors?

Cell membranes

Where are the amine (thyroid hormones) receptors?

nuclear

Polar =

Water soluble

Non-polar =

lipophilic

What is the solubility of proteins?

polar

What is the solubility of steroids?

Non-polar

What is the solubility of Amines (catecholamines)?

Polar

What is the solubility of amines (thyroid hormones)?

non-polar

What are examples of proteins/pepties?

Insulin, glucagon, prolactin, ACTH, gastric, and parathyroid hormone

What are examples of steroids?

Cortisol, aldosterone, estrogen, progesterone, and testosterone

What are examples of amines?

Catecholamines (epinephrine and dopamine) and thyroid hormones

Where does the autocrine signal to?

selfW

What does paracrine signaling signal to?

nearby cells

What is the naming of signaling based on?

how far it travels

What type of signaling do neurotransmitters that use local nerve signaling use?

paracrine signaling

Insulin is released into the bloodstream and acts on target cells throughout the body. What type of cellular communication is being used?

endocrine signaling

Insulin is released from the pancreas and binds to receptors on the cell membrane. How is insulin best classified?

Protein/peptide hormone

What molecular characteristic must synthetic thyroid hormone have to be effective?

Diffusion across the lipid bilayer

What peptide molecules are important for immune function and can act locally or go over long distances?

Cytokines

Ligands that can activate the receptor?

Agonist

Ligands that block activation?

antagonist

What is an agonist?

Ligands that activate the receptor

What is an antagonist?

Ligands that block activation

What are the three main types of cell surface receptors?

Ion channel-linked, G protein-linked, and enzyme-linked

What binding opens the ion channel, which allows ions to move down their electrochemical gradient?

ligand

How fast is ligand binding?

fast af

What receptors are widely distributed throughout the body and use second messengers to amplify cellular responses?

G-Protein coupled receptors

What can bind to G-protein receptors?

anything water soluble

How fast are G-protein coupled receptors?

fast

What receptors are commonly used in growth and metabolic signaling and amplify cellular responses through phosphorylation cascades?

Enzyme-linkedH

How fast do enzyme-linked receptors work?

slow

What triggers phosphorylation cascades?

tyrosine kinase

What does phosphorylation cascade cause?

Physiologic changes to cells

What signaling mechanism best explains why blood glucose gradually decreases over several hours?

Activation phosphorylation signaling pathways

What receptor type best explains the rapid cellular response to epinephrine?

G-protein coupled

Why can a small amount of epinephrine produce a large cellular response in target tissues?

Amplification via second messengers

What is the structure of ion-channel linked receptors?

Forms a pore in the membrane

What is the structure of G-Protein coupled receptors?

7 transmembrane domains

What is the structure of enzyme-lined receptors?

single-pass transmembrane receptor

What is the signal type of ion-channel-linked receptors?

Direct ion movement

What is the signal type of G-protein coupled?

second messenger cascade

What is the signal type of enzyme-linked?

phosphorylation cascafe

What are examples of ion-channel linked receptors?

Nicotinic ach receptor

What are examples of G-protein coupled receptors?

Catecholamines and glucagon

What are examples of enzyme-linked receptors?

leptin, insulin, and growth factor

What is produced from ATP to relay intracellular signals?

cAMP

How does the cAMP system start?

GPCR activates adenylyl cyclase

What are the second messengers for the cAMP system>

cAMP

What is the key activation of the cAMP system?

cAMP activates protein kinase A

What is the main intracellular effect of the cAMP systems?

phosphorylation of enzymes

What is the amplification strategy of the cAMP system?

one atp → many cAMP molecule

What is the source of signal for cAMP systems?

ATP

What is the source of the signal for phospholipase C?

PIP2

How does phospholipase C start?

GPCR

What are the second messengers for phospholipases C?

IP3 and DAG

What are the key acti