Exam 3 Signal Transduction 1

Front 1

hormone signaling acts by ... distance

Back 1

long

Front 2

which of the following second messengers also can serve as a primary messenger?
-cAMP
-cGMP
-NO

Back 2

NO

Front 3

what is this called?
-conversion of an extracellular signal or environmental stimuli from one physical/chemical form into another. Or more simply, the process by which a cell responds to an extracellular signal and affects change in the behavior of that cell

Back 3

signal transduction

Front 4

Signal transduction is important in ...genesis, reacting to your ..., simple cellular ..., and in pathologies

Back 4

embryo
environment
maintenance

Front 5

... are physical, chemical, or molecular in nature and can cause cells to respond in a multitude of ways (cell shape, metabolism, proliferation, movement, expression, apoptosis)

Back 5

external signals

Front 6

One signal binds to ... receptor; binding can result in a ... of effects

Back 6

one
multitude

Front 7

what is the first step in which a signal molecule is transformed or transduced into a usable form to stimulate a response? (signal binding can occur to extracellular or intracellular receptor)

Back 7

primary transduction

Front 8

what is this?
-series of events in which message is passed from one molecule to another
-cascades of intracellular signaling molecules (...)
-formation of second messengers

Back 8

relay
signaling cascade

Front 9

often during the signaling cascade the message is ... allowing for a larger and faster intracellular response.

Back 9

amplified

Front 10

-the signaling cascade can be ... along several different pathways at the same time.
-this distribution allows for a ... of the signal so that it may be relayed to a number of different intracellular targets (change in gene expression, change in cell shape)

Back 10

distributed
divergence

Front 11

each step of the signaling cascade is ... by other factors (external signals and/or second messengers)

Back 11

modulated

Front 12

... pathway very in complexity; simple and direct to extreme and complex branching

Back 12

signaling

Front 13

the 4 steps in which a message is passed from one molecule to another are...

Back 13

1)primary transduction
2)relay
3)amplification
4)distribution/divergence

Front 14

Flow of info during cell signaling:
-the ligand which is the primary messenger, hormone or growth factor, binds to a receptor located in the ...

Back 14

plasma membrane

Front 15

Flow of info during cell signaling:

-The binding causes a ... that in turn activates a secondary messenger (small molecules or ions that transmit signals from extracellular signals to the cell interior) that initiates a cascade of events in the interior of the cell

Back 15

conformational change

Front 16

Flow of info during cell signaling:
-... response: the secondary messenger will in some cases alter protein function that leads to a change in the cellular response (activation or inhibition of various pathways)

Back 16

fast

Front 17

Flow of info during cell signaling:
-... response: the secondary messenger may also impact gene expression

Back 17

slow

Front 18

The major players:
-extracellular or ... signals
-signal transduction ...
-variety of ... and ... enzymes (specific to the signaling pathway)
-... (molecules that are produced in the cytoplasm and move within the cell to induce another series of signaling)

Back 18

primary
receptors
membrane-bound
cytoplasmic
second messengers

Front 19

signaling can occur in what 3 ways?

Back 19

long distance
locally
direct contact

Front 20

Long distance hormones:
-chemical messengers that are distributed throughout the body
-produced by either ... or ... cells and secreted into body fluid; carried throughout the body in the ...
-act on a target cell that expresses a protein receptor ... for the hormone
-necessary in ... quantities (very effective in small amounts)
-usually regulated by hormone that is ... in nature (insulin and glucagon)

Back 20

endocrine
neurosecretory
bloodstream
specific
minute
antagonistic

Front 21

Local hormones: (1st type) = ... signals - local mediators

-signal molecules secreted by cells into its surrounding ... fluid
-affects target cells in the ... of the cell that secretes molecules
-local mediators include ... factors, cytokines and ...
-some cells can express receptors for the signal itself (... signaling). They self stimulate. Is common in immune system

Back 21

paracrine
interstitial
neighborhood
growth
eicosanoids
autocrine

Front 22

Local hormones: (2nd type) = synaptic signaling - ...

-release of these molecules into the synapse between a neuron and its target cell (neuron, muscle, etc.)

Back 22

neurotransmitters

Front 23

direct contact hormones:

-... of membranes
-no release of ... molecule involved
-... bound signal
-delivery of message when signal molecule in one cell membrane binds receptor molecule in another cell membrane
-... development

Back 23

interface
secreted
membrane
embryonic

Front 24

what are the 2 categories of signal transduction receptors?

Back 24

intracellular receptors
cell-surface receptors

Front 25

intracellular receptors:
-bind ... (lipids) signal molecules; tend to be ...
-... molecules readily translocate across lipid bilayers
-found in ... and ...

Back 25

hydrophobic
small
hydrophobic
cytoplasm
nucleus

Front 26

cell surface receptors:

-bind large ... signal molecules which are unable to cross cell membrane
-signal molecules bind to extracellular domains of receptor; receptor in turn generates ... signals

Back 26

hydrophilic
intracellular

Front 27

2 classes of receptors that bind either lipid soluble ligands or gases:

-cytoplasmic ... - change in gene expression

-cytoplasmic ... - produces second messenger cGMP

Back 27

steroid receptor
guanylyl cyclase

Front 28

which signal transduction receptor produces a trimeric G-protein?

Back 28

seven-helix

Front 29

which signal transduction receptor produces tyrosine phosphorylation?

Back 29

receptor tyrosine kinase

Front 30

the remaining cell surface receptors are:

-transmembrane
-bind ... soluble molecules: amines, peptides, proteins, glycoproteins
-effectors vary depending on ...

Back 30

water
receptor

Front 31

The number of different types of receptors is much (less than/greater than) the number of extracellular signals that act on them.

In other words, one signal molecule may act on a ... of different receptors

Back 31

greater than

variety

Front 32

what is this?
-a neurotransmitter
-acts as a vasodilator and as a vasoconstrictor - acts in 2 opposing ways

Back 32

acetylcholine

Front 33

acetylcholine binds to a variety of receptors:

1. Ligand-gated ion channels (... acetycholine receptor)

2. G-linked protein receptor (... acetylcholine receptor) - activate other ionic channels via second messenger cascade

Back 33

nicotinic
muscarinic

Front 34

side note:

Foreign substances target the various cell-surface receptors and interfere with normal physiology and sensations. These substances either ... the ligand and bind to the receptor or bind to the receptor at ... site, blocking or overstimulating the receptor's normal activity.
-it acts to ... the natural signal

Back 34

mimic
another
mimic

Front 35

in the heart muscle cell, acetylcholine acts as a ... and decreases the rate and force of contraction

Back 35

vasodilator

Front 36

in the salivary gland cell, acetylcholine binds to the receptor protein and causes ...

Back 36

secretion

Front 37

in the skeletal muscle cell, acetycholine acts as a ... and induces contraction

Back 37

vasoconstrictor

Front 38

acetylcholine is also a major player in the regulation of ...

Back 38

blood pressure

Front 39

what are small molecules formed in or released into the cytoplasm in response to an extracellular signal that helps relay the signal to the interior of the cell?

Back 39

second messengers

Front 40

what are the 4 categories of second messenger?

Back 40

cyclic nucleotides
lipid-derived 2nd messengers
calcium (Ca2+)
nitric oxide

Front 41

cyclic nucleotides:
-two cyclic nucleosides monophosphates - ... and ...
-cyclic nucleosides synthesized by cyclases from either ... or ...
-targets include protein kinase and cyclic nucleotide-gated ion channels

Back 41

cGMP and cAMP
GTP or ATP

Front 42

lipid derived second messengers:

-variety of lipid second messengers; concentrate on inositol 1,4,5-triphosphate (...), diacylglycerol (...), and arachidonate/eicosanoids, which are derived from lipids in membrane (...)
-primary sources of signaling molecules are phosphatidylinositol, phosphatidylcholine, and ...
-types of enzymes that generate lipid second messengers: phospholipases, lipid kinases, and lipid ...
-produced by most signaling pathways

Back 42

[IP3]
DAG
PIP2
sphingomyelin
phosphatases

Front 43

Calcium (Ca2+):

-cytoplasmic concentration dependent on opening/closing of ion channels that release ion from ... and pumps that remove ion from ...
-liberated from ... stores

Back 43

stores
cytoplasm
SER

Front 44

nitric oxide:

-unique means of transmitting ...

Back 44

signal

Front 45

steroid and thyroid hormones:

-steroid hormones are synthesized from ... (adrenal glands, testis, ovaries and placenta)
-thyroid hormones derived from ... (thyroid gland)

Back 45

cholesterol
tyrosine

Front 46

both steroid and thyroid hormones are ... signal molecules:

-readily pass through lipid membranes of target cells
-bind to hormone receptors located either in the cytoplasm or the ...
-hormone receptors regulate gene expression; normally present in ... form
-binding of hormone causes ... change leading to activation of receptor
-transcription of a set of genes either turned ON/OFF

Back 46

hydrophobic
nucleus
inactive
conformational

Front 47

steroid thyroid hormone NOTE:

There is no generation of a ... cascade or the formation of a ...

Each hormone will bind a different receptor in turn regulating a different set of ...; this evokes a variety of physiological responses specific for the hormone

Back 47

signaling
second messenger

genes

Front 48

acetylcholine causes relaxation of smooth muscle of blood vessels through the action of ...

-NO is indirectly produced by acetylcholine binding

Back 48

nitric oxide (NO)

Front 49

acetylcholine:

-is produced and secreted by ... cells
-binds (G-protein) receptor on endothelium and activates NO synthase, via the second messenger Ca2+, that converts arginine to NO and ...

Back 49

neurosecretory
citrulline

Front 50

Nitric oxide is dissolved gas produced by ... cells surrounding smooth muscle cells

Back 50

endothelial

Front 51

Nitric oxide:

-acts as a local mediator (... signaling)
-produced as a second messenger by endothelial cells
-formed by the action of ... that converts arginine into citrulline and NO
-NO diffuses to ... smooth muscle
-in smooth muscle, NO will activate Guanynyl cyclase which converts GTP to ...(second messenger)

Back 51

paracrine
NO synthase
neighboring
cGMP

Front 52

cGMP acts as a second messenger triggering the next series of activations in the cell that leads to the cellular change:
-cGMP ...
-cGMP-...

Back 52

protein kinase
gated ion channels

Front 53

NO is quickly converted into nitrates and ...

Back 53

nitrites

Front 54

cGMP is very similar in structure to another second messenger, ...

Back 54

cAMP

Front 55

cGMP:

-produced by activation of cytoplasmic guanylyl cyclase by ...
-targets cGMP-protein kinase that triggers a series of events that leads to the cytoskeletal rearrangements physiological changes necessary for ... of the cell

Back 55

NO
relaxation

Front 56

nitroglycerine and viagra (do/do not) mix

Back 56

DO NOT

Front 57

nitroglycerine (non-specific)
-used as a coronary artery ..., but is non specific and causes hypotension
-rapidly converted to NO and in turn to cGMP

Back 57

vasodilator

Front 58

Viagra (cialis and levitra-extended action):

-erectile dysfunction
-enhancement of penile erection by blocking ... of cGMP to 5'-GMP y cGMP phosphodiesterase

Back 58

degredation

Front 59

-NO is released by nerve terminal in the penis triggering localized blood-vessel ... leading to penile erection

-use of erectile dysfunction drug in association with nitroglycerin has been shown to cause ..., not responsive to fluid administration or vasopressors (antidiuretics which also increase peripheral vascular resistance leading to blood shunting via vasoconstriction)

Back 59

dilation
intractable hypotension

Front 60

Cell surface receptors: G-protein linked receptors:

-activate membrane bound G proteins (trimeric GTP-binding protein or G protein)
-... initiated through second messengers

Back 60

signaling cascade

Front 61

Cell-surface receptors: Enzyme-linked receptors:

-when activated, either act as ... or rely on associated enzymes for action
-enzymatic activity generates ...

Back 61

enzymes
second messengers