Question

Q. 34. 2. Circle the correct answers. Iron response proteins (IRP) are under allosteric regulations. Binding (iron/ iron response elements/ ferritin/ transferrin) (enables/ prevents) IRP binding to (iron/ iron response elements/ ferritin/ transferrin) and prevents (iron/ iron response elements/ ferritin/ transferrin) translation.

Answer 1

Answer 34:

So the state ment will be : Binding Iron prevents IRP binding to iron response elements and prevents transferrin translation.

Explanation:

As it is already given in the question that Iron response proteins (IRP) are under allosteric regulations.

• When the Iron is limited in the cell, IRPs binds to the 5' IRE ans repress the translation of Ferritin and also it binds to 3' IRE in TfR1mRNA induces the translation of TFR.
• when concentration of iron in the cell is high IRPs do not bind IREs and this results in the translation of Ferritin (5' IRE containing mRNA) and leads to the prevention of transferrin translation (degradation of TfR1mRNA)