Long Term Memory

Front 1

3 major pathways in the hippocampus

Back 1

entorhinal cortex-> granual cells of dentate gyrus (perforant path.) granual cells-> pyramidal of CA3 (mossy fiber path) cA3-> ca1 pyramidal cells (schaeffer colateral path)

Front 2

Describe LTP in the mossy fiber path.

Back 2

NMDAr (post-syn) not required. Rep. stimulation of granule cells leads to incr. amplitude of epsp in pyramidal cells. due to ca+ influx_>ca/caM activate AC makes cAMP activates PKA ,activates NT

Front 3

Describe LTP in the schaeffer collateral pathway

Back 3

postsynaptic and presynaptic (though induced by postsynaptic). depolarization of postsyn by several axons required=cooperativity. this is because of dual gating of nmda-receptors. Ca influx sets of PKA cascade- regulatory unit + mapk into nucleus, induce gene transcription cepb and ubiquitin hydrolase

Front 4

pka pathway

Back 4

G protein activates Adenylyl cyclase via alpha subunit. AC produces cAMP from ATP, cAMP activates PKA, PKA phosporylates target proteins, including creb1,2 and Kchannel, Ltype Ca channel

critical for late LTP- no PKA or CREB eliminates late LTP

Front 5

classical conditioning

Back 5

unconditioned (natural) wait 5s then conditioned stimulus. CS activates adenylyl cyclase and US activates serotonin receptrors coupled to ac. Third- retrograde signal back to presynaptic ell to increase NT release

Front 6

pkc pathway

Back 6

g protein

Front 7

phosphotase
phosphodiesterase
ubiquitin hydrolase

Back 7

dephosphorylates protein
chews up cAMP
chews up regulatory unit of PKA

Front 8

molecular evidence of camkinase II regulation importance in memory/ use tetO/temporal example

Back 8

Tetracycline to temporally (not regionally) restrict gene expression. TetO promoter of bacteria is controlling a camKii -const. active gene. This transgenic mouse is crossed with a mouse expressing tTA(transcription factor) controlled by a camKII promoter. TeA binds tetO and promotes camKii-active gene which causes mouse to go screwy and have learning problems- too much unregulated camkinase. Doxycycline pulls tTA off tetO and no longer is camkii continually generated

Front 9

NMDA-r1 regional knockout- evidence of importance of nmda receptor in learning and memory

Back 9

Cre Recombinase only expressed through CamKII promoter in CA1 cells---CRE then is available to catalyze the recombination of the lox P recognition sites

Front 10

BMP suppression molecules
TGF-beta

Back 10

Chordin, noggin, follistatin bind BMP and block it from blocking neural route of ectodermal development

Front 11

medial->lateral:dorsoventral axis
sensory info___
motor info__

Back 11

sensory,commisural=dorsal
motor, interneurons=ventral

Front 12

anteroposterior axs
caudal portion:___
rostral portion:___

Back 12

caudal portion: spinal cord
rostral portin: forebrain

Front 13

SHH patterns the
while BMPs pattern

Back 13

ventral neural tube (motor)

dorsal tube (sensory)

Front 14

shh expressed in floor plate and neural tube
bmp expressed in roof plate
t or f?

Back 14

true!

Front 15

how does SHH work

Back 15

SHH binds to receptor PTC and relieves the repression on second TM protein (smoothed). SMO regulates protein kinases and activates a class of transcription factors (gli proteins) which enter the nucleus and induce expression of a number of genes.

Front 16

levels of SHH and the ventral differentiation

Back 16

Low concentrations of SHH induce ventral neural tube cells to become ventral interneurons while higher SHH concentrations induce differentiation of ventral neural tube cells into motor neurons and very high SHH levels induce cells to become floor plate cells.

Front 17

how does bmp work?

Back 17

BMPs activate transmembrane Ser-Thr kinases and phophorylates SMAD a transcription factor- goes to nucleus and interacts with other transcription factors

Front 18

how do dorsal and ventral patterning differ, mechanistically?

Back 18

Ventral patterning is regulated by different concentrations of SHH inducing different cell types.
In contrast, dorsal patterning involves several different members of the BMP family , each of which appears to induce a particular cell type.

Front 19

name four types of ventral neurons that are induced by BMP

Back 19

motor neurons, ventral interneurons, dopaminergic, serotonergic

Front 20

lamellipodia

Back 20

motile end of axon/growth cone/ microtubules and actin mesh

Front 21

extracellular matrix cues

Back 21

lamella-11 different types in ECM and integrins on cone surface and bind cytoskeletal proteins in mesh- some specificity for type

Front 22

cell:cell interactions
Cadherins (Ca2+-requiring) and immunoglobulin-like adhesion molecules.

Back 22

Cadherins homophilic reactions
immunoglobulin: even more than 100 types, but bind to more types
both link to cytoskeleton and trigger intracellular pathways

Front 23

chemotaxis
netrins

Back 23

chemotaxis- gradient of chemicals

Intracellular factors can influence responses to netrins. For example, PKA activation leads to growth cone attraction to netrins; however, if PKA is inactive, repulsion towards netrins is seen instead.
can also be a repellant

Front 24

ephrins

Back 24

inhibitory signals and Eph kinases are receptor tyrosine kinases found on growth cones.

Front 25

Semaphorins
neuropilin and plexins

Back 25

Semaphorins (15 identified) such as collapsin-1 cause growth cone collapse and growth in the opposite direction.
receptors for semaphorins

Front 26

neurotrophic factors

Back 26

facilitate growth and repair

Front 27

cytokines

Back 27

small proteins, that have specific effect, like hormones

Front 28

differentation of neural crest cells into neurons - environmental signals...

Back 28

BMP proteins signal the expression of a protein called mash-1 which is a transcription factor required for generation of central and peripheral neurons.

Front 29

differentation of neural crest cells into glia - environmental signals...

Back 29

GGF (glial growth factor) is expressed on the surfaces of autonomic neurons when they first differentiate. It inhibits neurogenesis on nearby neural crest cells, directing them to follow the glial cell differentiation pattern

Front 30

Differentiation of Glial cells
_maintains progenitor cells
__ CREATES ASTROGLIA

Back 30

__PDGF__maintains progenitor cells
CNTF

Front 31

NEURONS OF CORTEX are generated in the ___ zone

and are created in what order?

Back 31

ventricular

Cortical neurons are generated in an inside-first, outside-last order.

Front 32

transplantation of cells depending on their cell cycle

Back 32

young cortical progenitor cells remain sensitive to time-dependent environmental signals that determine their fates. As they become postmitotic they become committed to a specific fate.

Front 33

an inadequate concnetration of neurotrophic factor secreted by target cells leads to

Back 33

apoptosis

Front 34

neurotrophic factors include bdnf,ngf,ctnf,interleukins, ec. and bind to 2 receptor types:- -

Back 34

p75NTR-binds all factors and tyrosine kinases- more specific to particular factor

Front 35

In the presence of neurotrophic factors and bound tyrosine kinase receptor...

Back 35

bcl2 supresses acaf which usually activates caspase (through cleavage)

Front 36

downstream effect of neurotrophin and cytokine binding

Back 36

neurotrophins and cytokines promote the dimerization of receptors and the activation of protien tyrosine kinases

Front 37

endogenous apoptosis program

Back 37

Sympathetic neurons in culture are maintained by NGF. Removal of NGF leads to apoptosis, but not if protein or RNA synthesis is blocked when NGF is removed. This suggests that neurotrophins antagonize an endogenous death program.
cell death genes- CED- are required for cell death

Front 38

apaf is...

Back 38

evil
leads to cleavage and activation of caspases