Molecular model of ferritin

Exploring storage proteins

Like putting money in the bank, living things store amino acids for later use

Organisms store proteins as a source of amino acids and metal ions for use later in life. These so-called ‘storage proteins’ are important in development. Plant seeds contain storage proteins to provide amino acids for use in germination and seedling growth. In animals, storage proteins include ovalbumin, which is found in egg white, and casein, which is found in milk.

Ferritin is another storage protein and is found in nearly all living things. It is a globular protein that stores iron intracellularly (inside the cell).

Doctors measure the ferritin level in the blood if they suspect a person of having iron-deficiency anaemia. This is a condition in which low iron can cause a lack of healthy red blood cells.

Lead image:

The iron storage molecule ferritin consists of 24 subunits arranged in a spherical shell around a central cavity.

Peter Artymiuk/Wellcome Images CC BY NC ND

About this resource

This resource was first published in ‘Proteins’ in January 2014.

Cell biology, Health, infection and disease, Biotechnology and engineering
Education levels:
16–19, Continuing professional development