BIOL 2021 Lecture Notes - Lecture 12: Creb-Binding Protein, Adenylyl Cyclase, Phosphodiesterase
13 May 2018
School
Department
Course
Professor
• Fig 15-27 cAMP pathway
• Table 15-1 cAMP responses:
o Effects of PKA activation:
o 1) rapid effects in seconds (ex: glycogen metabolism in muscles).
o In unstimulated cells, the phosphodiesterase keeps the local cAMP
concentration low, so that the bound PKA is inactive; in stimulated cells,
cAMP concentration rapidly rises, overwhelming the phosphodiesterase
and activating the PKA.
o What turns off rapid effects?
o a) cAMP phosphodiesterase destroys cAMP.
o b) protein phosphatases dephosphorylate protein activated by PKA.
o 2) slow responses in hours, change in gene transcription.
• Vid 15.2 cAMP signaling, cAMP is activated and activates PKA, which has 2
regulatory and 2 catalytic subunits. Which will separate → activating CREB.
• Fig 15-27 cAMP pathway
o PKA phosphorylates CREB protein.
o CRE = cAMP response element = DNA regulatory region near genes to be
transcribed.
o CREB = CRE-binding protein → phosphorylated and activated by cAMP.
o CBP = CREB binding protein = transcriptional co-activator.
o Short term signal, transformed into a long term change inside the cell.
Might even cause a permanent change in the cell.
find more resources at oneclass.com
find more resources at oneclass.com
