Invertebrate models in Neuroscience

Question 1

What are the 3 advantages of invertebrate model systems?

Answer 1

• large diameter neurons, facilitate microelectrode recording -simple nervous systems, enhancing tractability of neuronal circuitry -well defined behaviours

Question 2

Hodgkin and Huxley (1952)

Answer 2

Intracellular recording of APs from giant squid axons, using voltage clamp to seperate ionic currents.

Question 3

Hodgkin and Huxley (1952) diagram

Answer 3

Question 4

Katz (1967)

Answer 4

Calcium hypothesis for neurotransmitter release- at equilibrium potential for calcium, no transmitter is released, calcium entry not change in transmembrane electric field is responsible for neurotransmitter release

Question 5

Choi (2014)

Answer 5

Gene knockout studies in D. melanogaster show spontaenous release but not evoked neurotransmission is required for the structural maturation of glutamatergic synapses.

Question 6

Kandel

Answer 6

Habituation of the aplysia gill withdrawral response due to decrease in synaptic strength between sensory and motor neurons

Question 7

Martin (1997)

Answer 7

Cultured single bifurcated aplysia sensory neuron, making synapses with 2 spatially seperated motor neurons. Perfuse serotonin onto one branch, show that single axonal branch can undergo long term branch-specific facilitation. Depends on CREB mediated transcription and involved growth of new connections exclusively at the treated branch

Question 8

Miller (1980s)

Answer 8

Hyperpolarised cells in this somatogastric ganglion of lobster - pattern generation continues until endoenous bursters inactivated. Endogenous oscillator model over network activity model

Question 9

Auluck (2002)

Answer 9

Dopaminergic neuronal loss in D. melanogaster when A-syn expressed. Directed expression of Hsp70 prevented dopaminergic neuronal loss associated with a-syn deposition

Question 10

Cohen (2006)

Answer 10

Aggregation mediated Abeta1-42 toxicity reduced when ageing slowed by decreased IGF-1 like signalling. Pathway central to longevity in worms, suggestive of mechanistic link between aging and proteotoxicity

Question 11

Nguyen (2015)

Answer 11

CGAMP + confocal to image whole head NS of C.elegans turning behaviour activity correlates.

Question 12

Benzer

Answer 12

Random mutation studies on drosophila, short and long periods map to genes, then identify the components of the circaidian clock

Question 13

Takuchi (2015)

Answer 13

Drosophila overexpress aggregation-prone proteins, express chaperones, improves proteostasis in other cells, presumably through exosome signalling.