Regulation of Glycogen metabolism
6 important questions on Regulation of Glycogen metabolism
How is glycogen metabolism regulated?
- control from outside the cell by (de)phosphorylation
Metabolites: AMP/ATP, glucose 6-phosphate, glucose
- control from within the cell by allosteric regulation
What is the difference between GP a and b?
- a: active state → phosphorylated phosphorylase
- b: less-active state → dephosphorylated phosphorylase
Both the a and b forms of GP can exist in the relaxed (R) state or tense (T) state.
- R (active) state → blue line is not blocking the active site
- T (inactive) state → blue line is blocking the active site
In which organs are the 2 isozymes of GP and what is their difference?
Liver phosphorylase
- has only a form and undergoes the R to T transition in the presence of glucose (inactivating it)
- acts as a glucose sensor when glucose binds it tells the GP to stop glycogen breakdown
Muscle phosphorylase
- a low energy charge (high AMP, low ATP) favours the transition of R (active) state
- a high concentration of ATP or glucose 6-phosphate favours transition of T (inactive) state
- calcium and adrenaline are hormones which react in muscle
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
For my 1st exam I got a C. Then, I started looking for ways to learn better and I came across Study Smart. Since then I have scored a A+, A, A- and another A. I highly recommend it to everyone who wants to hear it. I am so happy with it!!
I was struggling to finish all my first-year subjects for 3 years. Then I discovered Study Smart, which helped me to finish all of them within 3 months.
Because of StudySmart, things are going well in many ways. Before, I always had study stress and no time for anything. Now I feel calm and confident (because of the program). I used to score a B, now I usually score an A or A+.
Hey Chris, I really want to thank you very much for developing the platform, I usually got around C for my exams, now I scored an A+, an A and a A- !!
Since using Study Smart, my average has increased significantly. I even completed a statistics course with a A+ while I'm bad at statistics. I took on extra courses this year, because of Study Smart. Thanks so much!
Ever since I started studying with StudySmart I passed all my exams !!! No more re-sits!! At first, I was happy with a pass and now I only get good grades. Many thanks!
I aced all the courses I studied with Study Smart. For law, I first scored a D, and now an A! I’m 100% sure that I’ll pass all the courses I study with Study Smart.
I always thought I studied well. My grades were fine. I could never have imagined that applying these study skills would have such a huge and direct impact on my grades, my speed and the pleasure I have in learning.
For the first time, I finally feel totally confident about the way I learn. I have the perfect overview and make great progress in terms of speed and the grades I get. Thanks, Chris!
I immediately started to enjoy learning again, and my grades soared. All of a sudden, everything went better. I highly recommend Study Smart to all students..
Being able to create my materials online made the process of studying so much smoother and quicker. I no longer have to spend a huge amount of my time on creating my summaries.
At first, my notes were a mess. Now I use Study Smart to take my notes in a perfectly structured way. It helps me to save a lot of time and do other things I enjoy.
Students that study with Study Smart get better grades. The system applies all the learning methods in such a way that both well-performing students and students who struggle perform much better.
Hi Chris, I would like to thank you very much. Last year I scored C on a course, and this year I got an A+ thanks to your method! Thank you very much!
The largest effect is that my child is more enthusiastic about school! Every parent wants their children to be happy at school, Study Smart made it happen.
In high school, I failed several exams, and that has really changed now. I actually needed this tool very much back then. Since I started studying with StudySmart, I haven't had any D's. My average score is now an A and those are results I would have never had in the past
With my old method, I passed only 3 out of 8 courses. Since I started taking my notes digitally in Study Smart, I have passed all my courses on the first try. For me, StudySmart takes away the stress of wondering if I will pass or not.
Thanks to StudySmart, I passed all my exams, and with better grades than before! On top of that, I have mastered a very good study method now, which I am confident will help me earn my degree.
How is the glycogen synthesis and breakdown regulated (enzymes)?
Explain the regulation of Glycogen synthase by protein phosphatase 1 (PP1) in muscle and liver
- the catalytic subunit PP1 is bound to the regulatory subunit, Gliver
- Glucose brings GP in the T (inactive) state, allowing PP1 to dephosphorylate and inactivate GP
- Free PP1 inactivates GP but activates GS (eaten/insulin)
Muscle (during exercise or fasting)
- the catalytic subunit PP1 is active while bound to the regulatory subunit, Gmuscle
- PKA phosphorylates Gmuscle, such that PP1 is releaed and becomes less active
- PKA also phosphorylates and activates an inhibitor of PP1
- under these condition, GP and GS can shift to the phosphorylated form
- GP active
- GS inactive
What are the 6 glycogen storage diseases and due to which enzyme?
- Von Gierke: glucose 6-phosphatase (liver, kidneys)
- Pompe: alfa-(1,4)-glucosidase (all organs)
- lysosome full of glycogen
- Cori: debranching enzyme (muscle, liver)
- Andersen: branching enzyme (liver, spleen)
- McArdle: glycogen phosphorylase (muscle)
- Hers: glycogen phosphorylase (liver)
Try our study magic for free
a PDF, study it super fast
- No sign up, email or credit card needed!
- AI makes unlimited flashcards
- Get unlimited quizzes and tests
- Ask AI anything
- No sign up, email or credit card needed!
- Have and keep perfect overview
- Make flashcards, notes and mind maps
- Review, test and score!
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
