Year: 2017
Type: dissertation
Abstract: cAMP and cGMP are universal second messengers and have been implicated in synaptic plasticity underlying learning and memory. Pharmacological and genetic manipulations highlight the role of postsynaptic cAMP/cGMP in synaptic plasticity; however these techniques alone lack the precision to understand their rapid and dynamic spatiotemporal roles. To non-invasively control the rapid molecular activity in living neurons, I developed genetically engineered photoactivatable PDE4 (PhPDE4) and PDE5 (PhPDE5) to independently degrade cAMP/cGMP by light. To optimize their light-dependent activities, I validated their single-photon and two-photon photoactive properties in vitro. These enzymes showed substrate specificity and rapid millisecond level photoactivation. For in vivo application, I demonstrated the suppression effect of cAMP in synapse structural plasticity by two-photon photoactivation of PhPDE4. In combination with bacterial photoactivatable enzymes (PAC, BLGC) to enhance cAMP/cGMP signaling, these novel light sensitive enzymes will enable us to understand the rapid spatiotemporal role of cAMP/cGMP in synaptic plasticity and brain function.
Source: TSpace (University of Toronto)
Author: Fiona Bergin
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2917366972