Erythroid 5‐aminolevulinate synthase mediates the upregulation of membrane band 3 protein expression by iron

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. Copyright © 2010 John Wiley & Sons, Ltd.

铁缺乏会导致3个蛋白在红细胞中的异常表达和功能，但是潜在的机制仍然是弹性的。在频带3的表达上进行EALAS的加密通过实时RT-PCR诱导的蛋白质和蛋白质印迹在MRNA和蛋白质水平的表达中，在EALAS-SHRNA转染的K562细胞中，蛋白质比对照细胞中的表达最低。这些结果首次表明铁和铁调节系统调节红细胞膜蛋白的表达。