The importance of eukaryotic ferritins in iron handling and cytoprotection

Ferritins, the main intracellular iron storage proteins, have been
studied for over 60years, mainly focusing on the mammalian
ones.Thisallowedtheelucidationofthestructureoftheseproteins
and the mechanisms regulating their iron incorporation and
mineralization.However,ferritinispresentinmost,althoughnot
all, eukaryotic cells, comprising monocellular and multicellular
invertebratesandvertebrates.Theaimofthisreviewistoprovide
anupdateonthegeneralpropertiesofferritinsthatarecommonto
variouseukaryoticphyla(exceptplants),andtogiveanoverview
on the structure, function and regulation of ferritins. An update
on the animal models that were used to characterize H, L and
mitochondrialferritinsisalsoprovided.Thedatashowthatferritin
structure is highly conserved among different phyla. It exerts an
important cytoprotective function against oxidative damage and
playsaroleininnateimmunity,whereitalsocontributestoprevent
parenchymal tissue from the cytotoxicity of pro-inflammatory
agonists released by the activation of the immune response
activation. Less clear are the properties of the secretory ferritins
expressed by insects and molluscs, which may be important for
understanding the role played by ferritin in mammals.