Suppose you have new inhibitors of signalling enzymes in the sea slug, Aplysia c

Question

Suppose you have new inhibitors of signalling enzymes in the sea slug, Aplysia californica. You possess a protein phosphatase inhibitor that specifically inhibits the enzyme that dephosphorylates CREB. You also have a specific adenylyl cyclase inhibitor that blocks production of cyclic AMP. Suppose you fed a group of sea slugs phosphatase inhibitor pellets a few minutes before each “ training session” where you induce the sensitization of the gill withdrawal reflex. A second group of slugs gets fed the adenylyl cyclase inhibitor pellets. Finally, a third group of slugs are fed Fruity Pebbles (a breakfast cereal that resembles the pellets) as a control. Which group of slugs would form a long-term memory the fastest, i.e. become sensitized after the fewest repetitions of the routine? Which would be slowest to learn? Please explain.

Explanation / Answer

The cAMP responsive element binding protein (CREB) is a nuclear protein that modulates the transcription of genes with cAMP responsive elements in their promoters. Increases in the concentration of either calcium or cAMP can trigger the phosphorylation and activation of CREB. This transcription factor is a component of intracellular signaling events that regulate a wide range of biological functions, from spermatogenesis to circadian rhythms and memory.

The fastest memory would be formed by the group of slugs those were fed with the phosphastase inhibitor because CREB is the one that is responsible for the long term memory. And the phosphastase inhibitor is the inhibitor of the enzyme that dephosphorylates the CREB thus inactivating it that leads to no long term memory. Since they are fed with the inhibitor of that enzyme the expression of CREB increases several fold and leads to fastest long term memory formation

The slowest slugs would be those were fed with the adenyl cyclase inhibitor because cAMP is the one who helps in phosphorylation of CREB and thus long term memory. Since cAMP itself is getting inhibited then there will be no formation of long term memory.

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.