Enwk1- 1-9 Biochem White Signal Transduction

Front 1

Example of a paracrine signal released

Back 1

neurotransmitter

Front 2

direct cell signal example

Back 2

immune cells (Ag presenting cells to T cells)

Front 3

In signal transduction what is the slow response refering to in reference of response?

Back 3

changes in amounts of proteins by change in expression of genes

Front 4

What signal is released from fat to signal hypothalamus when you are full?

Back 4

leptin

Front 5

main categories of signaling module (ligand)

Back 5

Can be proteins, small peptides, amino acid derivatives, hydrophobic molecules (steroid hormones like estrogen)
main categories
small lipophilic molecules"- steroid hormones,
water solublle molecules: growth factors

Front 6

describe the basic structure of g-proteins

Back 6

heterotrimeric proteins composed of 3 subunits- alpha, beta, gamma

Front 7

name the enzymes that are target of 2ndary messengery cAMP

Back 7

FLAT CHAMP
(FSH, LH, ACTH, TSH, CRH, hCH, ADH (V2 receptor), MSH, PTH, calcitonin, GHRH, glucagon

Front 8

describe the process of g-coupled signal transduction

Back 8

1. signal ligand binds to ligand alters conformation of receptor exposing binding site for Gs protein
2. activated receptor binds to G-protein (acts as GEF)
3. Ga releases GDP and binds GTP, and dissociates from GBgamma
4. Ga binds and activates adenylyl cyclase (which produces many molecules of cAMP)
5. Ga hydrolyses GTP to GDP, dissociates from adenlyl cyclase and binds GBgamma (inactive)

Front 9

what generates cAMP

Back 9

adenylyl cyclase

Front 10

Explain how vibria cholerae works with a G-protein system to cause problems

Back 10

keeps the G alpha in GTP active form, which makes pathway always active and pumps Cl and water out of cells into intestines

Front 11

what removes cAMP?

Back 11

phosphodiesterases

Front 12

Describe the role of GRKs

Back 12

G protein receptor kinases
- GRKs phosphorylates the receotpr such that another protein called arrestin will bind to the 3rd intracellular loop and prevents Ga from interacting with the third loop and prevents Ga from interacting with the third loop

Front 13

Example of paracrine signaling with both receptor and effector being enzymes

Back 13

Guanidyl cyclase produces cGMP (2nd messenger) which influences muscle relaxation in circulatory system: causinging increase in blood flow

Front 14

Which signaling is cGMP involved in?

Back 14

NO (EDRF) and ANP

Front 15

What type of receptors and pneumonic involve phospholipase C

Back 15

Gq subunit
HAVe 1 M&M
H1,a1,V1,M1,M3

Front 16

What does phospholipase C do and result in?

Back 16

Gq activates it which cleaves PIP2 leading to 2ndary messengers
1. DAG--> protein kinase C
2. IP3--> increase calcium release from ER

Front 17

type of G proteins

Back 17

Gas, Gai, Gao, Gaq, Golf

Front 18

2ndary messengers of g proteins

Downstream effectors

Back 18

cAMP, DAG, IP3, Ca

PKA, PKC, and gated-ion channels

Front 19

mutation in hemochromoatosis?

What pathway does the gene in question work through?

Back 19

HFe gene cys282 to Tyr (C282Y)

HFe works through the Smad pathway

Front 20

What 2ndary messengers activate protein kinase C

Where do they come from?

Back 20

1. DAG-> PIP2
2. Ca released iPS-> PIP2

Front 21

As a secondary messenger Ca binds to protein kinase C and what other protein?

Back 21

calmodulin which can bind to a number of cellular proteins to activate their functions

Front 22

What are receptor tyrosine kinases (RTK) used for?

Back 22

used for response to growth factor: mediate growth factor signals
(allows cells to grow and proliferate in culture)

Front 23

RTK (receptor tyrosine kinases) components include?

Back 23

1. extracellular domain
2. transmembrane domain
3. cytoplasmic domain- transmits signal through tyrosine kinase domain
4. adds phosphate to tyrosine on proteins

Front 24

Run from start to insanity steps of Receptor tyrosine kinase (RTK) activity

Back 24

1. growth factor (GF) binds to receptor of RTK and dimerization occurs
2. Autophosphorylation occurs and cross phosphorylation
3. Binding of adaptor proteins such as Grb2 (SH2 region)
4. SH3 region of Grb2 binds to proline in SOS which binds to Ras
5. Ras binds to Raf after guanine nucleotide exchange occurs
6. insanity

Front 25

Once things involving RTK activity get "insane" explain the steps...

Back 25

1. Ras initiates MAP kinase cascade
2. MAP kinase kinase kinase (Raf) becomes MAP kinase kinase
3. MAP kinase kinase become MAP kinase
4. MAP kinase enters the nucleus which leads to gene transcription

Front 26

Describe the JAK-STAT receptor associated form of tyrosine kinase...

Back 26

1. receptors bind cytokines, dimerize and bind JAKs
2. JAKs phosphorylate each other and the receptor
3. Receptor binds and phosphorylates STATs
4. STATs dissociate from receptor dimerize translocate to nucleus

Front 27

What pathways use JAK-STAT model?

Back 27

erythropoeitin

but remember PiG (Prolactin, cytokine (IL-2, 6, 8), GH)

Front 28

Explain the serine-thronin receptor and Smad form of pathway

What metabolic pathway does this?

Back 28

Used in iron metabolism (hepcidin)
1. ligand binds to monomer
2. monomer forms herterodimer and cross phosphorylates to activate receptor
3. receptor phosphorylates R-Smad protein
4. R-Smad complexes with Co-Smad and migrates to nucleus