α-Synuclein expression is modulated at the translational level by iron

TY - JOUR

T1 - α-Synuclein expression is modulated at the translational level by iron

AU - Febbraro, Fabia

AU - Giorgi, Marcello

AU - Caldarola, Sara

AU - Loreni, Fabrizio

AU - Romero-Ramos, Marina

PY - 2012

Y1 - 2012

N2 - Several studies have suggested an interaction between α-synuclein protein and iron in Parkinson's disease. The presence of iron together with α-synuclein in Lewy bodies, the increase of iron in the substantia nigra and the correlation between polymorphism of the several genes implicated in iron metabolism and Parkinson's disease, support a role for iron in the neurodegeneration. Analysis of post mortem brains revealed increased amount of insoluble α-synuclein protein despite unchanged/reduced levels of α-synuclein mRNA in Parkinson's disease. Interestingly, on the basis of the presence of a putative iron responsive element in the 5'-UTR, it has been suggested that there is a possible iron-dependent translational control of human α-synuclein mRNA. Considering the similarity between the sequences present in human α-synuclein mRNA and the ferritin iron responsive element, we postulated that iron deficiency would decrease the translation of α-synuclein mRNA. Here we used HEK293 cells treated with iron chelator deferoxamine or ferric ammonium citrate to verify the possible iron-dependent translational control of human α-synuclein biosynthesis. We show that the amount of polysome-associated endogenous human α-synuclein mRNA decreases in presence of deferoxamine. Our data demonstrate that human α-synuclein expression is regulated by iron mainly at the translational level. This result not only supports a role for iron in the translational control of α-synuclein expression, but also suggests that iron chelation may be a valid approach to control α-synuclein levels in the brain.

AB - Several studies have suggested an interaction between α-synuclein protein and iron in Parkinson's disease. The presence of iron together with α-synuclein in Lewy bodies, the increase of iron in the substantia nigra and the correlation between polymorphism of the several genes implicated in iron metabolism and Parkinson's disease, support a role for iron in the neurodegeneration. Analysis of post mortem brains revealed increased amount of insoluble α-synuclein protein despite unchanged/reduced levels of α-synuclein mRNA in Parkinson's disease. Interestingly, on the basis of the presence of a putative iron responsive element in the 5'-UTR, it has been suggested that there is a possible iron-dependent translational control of human α-synuclein mRNA. Considering the similarity between the sequences present in human α-synuclein mRNA and the ferritin iron responsive element, we postulated that iron deficiency would decrease the translation of α-synuclein mRNA. Here we used HEK293 cells treated with iron chelator deferoxamine or ferric ammonium citrate to verify the possible iron-dependent translational control of human α-synuclein biosynthesis. We show that the amount of polysome-associated endogenous human α-synuclein mRNA decreases in presence of deferoxamine. Our data demonstrate that human α-synuclein expression is regulated by iron mainly at the translational level. This result not only supports a role for iron in the translational control of α-synuclein expression, but also suggests that iron chelation may be a valid approach to control α-synuclein levels in the brain.

U2 - 10.1097/WNR.0b013e328354a1f0

DO - 10.1097/WNR.0b013e328354a1f0

M3 - Journal article

C2 - 22581044

SN - 0959-4965

VL - 23

SP - 576

EP - 580

JO - NeuroReport

JF - NeuroReport

IS - 9

ER -