Iron is a vital yet potentially toxic substance. How are optimum levels of iron maintained in mammalian cells. An iron binding protein known as iron regulatory protein (IRP) plays a key role in this regard. Which of the following statements about iron regulatory protein (IRP) is not true? when iron is limiting the IRP binds to iron response element (IRE) in the 3' UTR of the transferrin receptor mRNA and inhibits translation when iron is limiting IRP binds to the iron response element (IRE) in the 5' UTR of the ferritin mRNA and inhibits translation. when iron is in excess, it binds to IRP and prevents it from binding to iron response element (IRE) of ferritin and promotes translation. Thus, more ferritin is made when iron is high.
Added by Spencer C.
Close
Step 1
When iron is limiting, the IRP binds to the IRE in the 3' UTR of the transferrin receptor mRNA and inhibits translation. This statement is true because when iron levels are low, IRP binding to the IRE in the 3' UTR of the transferrin receptor mRNA stabilizes the Show more…
Show all steps
Your feedback will help us improve your experience
Dominador Tan and 71 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Although essential, iron is also potentially toxic. It is maintained at optimal levels in mammalian cells by the actions of three proteins. Transferrin binds to extracellular iron ions and carries it within the bloodstream; the transferrin receptor binds iron-loaded transferrin and brings it into the cell; and ferritin binds iron within the cell to provide an intracellular storage site. Both ferritin and the transferrin receptor are regulated by mechanisms that are similar and complementary. a. Do a bit of research and describe in general how the concentrations of ferritin and transferrin receptor are regulated by iron levels. b. You will (hopefully) find that the two are regulated by a similar mechanism, but in an opposite fashion. Explain how this opposite regulation in response to iron levels makes biological sense.
Madhur L.
Although essential, iron is also potentially toxic. It is maintained at optimal levels in mammalian cells by the actions of three proteins. Transferrin binds to extracellular iron ions and carries it within the bloodstream; the transferrin receptor binds iron-loaded transferrin and brings it into the cell; and ferritin binds iron within the cell to provide an intracellular storage site. Both ferritin and the transferrin receptor are regulated by mechanisms that are similar and complementary. Do a bit of research and describe in general how the concentrations of ferritin and transferrin receptor are regulated by iron levels. You will (hopefully) find that the two are regulated by a similar mechanism, but in an opposite fashion. Explain how this opposite regulation in response to iron levels makes biological sense.
Adi S.
The following questions pertain to iron regulation of ferritin and transferrin translation. Describe, in detail, what would happen in the following situations (note: when I talk about iron concentration, I am talking about the iron concentration INSIDE the cell). a) Regulation of transferrin translation when iron is high AND mutation such that iron cannot bind aconitase b). Regulation of ferritin translation when iron is low and mutation such that aconitase cannot recognize the IRE and cannot bind.
Sri K.
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
Watch the video solution with this free unlock.
EMAIL
PASSWORD