Expression Of MicroRNA-144/451in Normal And β-thalassemic Erythropoiesis

Objective:To investigate the expression of miR-144/451in normal and β-thalassemic erythropoiesis and the effect of the miR-144/451expression on P-thalassemic anemic phenotype.Methods:1. In order to study miR-144/451expression in β-thalassemic erythropoiesis,we bred and identified sufficient number of β-thalassemia mice and miR-144/451knock-out β-thalassemia mice generating humanized β-thalassemia mice models.2. In order to clarify miR-144/451expression in normal and β-thalassemic erythropoi esis, the following experiments were performed:first, we bred3-6months-old β-thalasse mia mice and wild-type mice as control.we took the14.5-days fetal liver of the β-thala ssemia mice and wild-type mice and screened the different expression of microRNAs usi ng miRNA microarray;then we examined the peripheral blood expression of miR-144/451of the two group using qRT-PCR;at last,we detected the expression of miR-144/451in bone marrow cells of the two group using qRT-PCR.3. In order to observe the effect of the miR-144/451expression on β-thalassemic an emic phenotype, First, we we bred3-6months-old β-thalassemia mice and miR-144/451knock-out β-thalassemia mice, and the erythrocyte indices are detected using HEMAVET950animal blood analyzer; Then, we observed the spleen for histological comparison.Results:1. After6months’breeding and identification:About200filial generation mice were bred and genotypic identification showed aproportion of β-globin+/+miR-144/451+/+mice of51.3%, p-globin+/-miR-144/451+/+mice of28.3%and p-globin+/-miR-144/451-/-mice of2.5%. the number increasing by nearly three times over the previous2. MiRNA microarray showed that,miRNAs were differentially expressed in the β-tha lassemia mice fetal liver, miR-144/451was up-regulated obviously. Peripheral blood expre ssion of miR-144/451in β-thalassemia mice was higher than in wild-type mice, in bone marrow cells also increased the level of miR-144/451in β-thalassemia mice.3. The complete blood counts and the spleen histological comparison of mice indicat ed that, the anemic phenotype of miR-144/451knock-out β-thalassemia mice had a meani ngful improvement compared with the β-thalassemia mice.Conclusions:Our results suggested that β-thalassemic erythropoiesis have a dysregulated miRNA-144/451expression program, andp-thalassemic anemic phenotype is improved downloading the miR-144/451expression. Analysis of miR-144/451is a relevant approach to determin e abnormalities of β-thalassemic erythropoiesis. And miR-144/451may become a new dia gnostic and therapeutic methods for human β-thalassemia.