title: Erythroid 5-aminolevulinate synthase mediates the upregulation of membrane band 3 protein expression by iron.
abstract: Iron deficiency leads to abnormal expression and function of band 3 protein in erythrocytes, but the underlying mechanisms remain elusive. The mRNA of erythroid-specific 5-aminolevulinate synthase (eALAS) contains an iron response element and the eALAS protein is an important mediator of iron utilization by erythrocytes. In this study, we investigated the effect of short hairpin RNA (shRNA) mediated silencing of eALAS on the expression of band 3 protein induced by iron. By real-time RT-PCR and Western blot we showed that at mRNA and protein level iron-induced expression of band 3 protein was lower in eALAS-shRNA transfected K562 cells than in control cells. Of note, the lowest expression was detected in K562 cells cultured in iron deficiency condition (p < 0.01). Thus either iron deficiency or depletion of eALAS could suppress the expression of erythroid band 3 protein. These results demonstrated for the first time that iron and the iron-regulatory system regulate the expression of the erythrocyte membrane proteins.
authors.affiliation: Department of Hematology, Changhai Hospital, Shanghai, China.
authors.forename: Qianchuan
authors.initials: Q
authors.lastname: Huang
authors.forename: Jinying
authors.initials: J
authors.lastname: Li
authors.forename: Weihua
authors.initials: W
authors.lastname: Feng
authors.forename: Yanqun
authors.initials: Y
authors.lastname: Xu
authors.forename: Zhenxia
authors.initials: Z
authors.lastname: Huang
authors.forename: Shuqing
authors.initials: S
authors.lastname: Lv
authors.forename: Hong
authors.initials: H
authors.lastname: Zhou
authors.forename: Lei
authors.initials: L
authors.lastname: Gao
mesh_terms: D000624:5-Aminolevulinate Synthetase / Q000235:genetics / Q000378:metabolism*; D001457:Anion Exchange Protein 1, Erythrocyte / Q000378:metabolism*; D015536:Down-Regulation; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D007501:Iron / Q000494:pharmacology*; D020014:K562 Cells; D034622:RNA Interference; D015854:Up-Regulation
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D007501:Iron; D000624:5-Aminolevulinate Synthetase