Identification of a Novel Indel Mutation in GATA-1 Gene In Vivo and Verified Its Defective Function in Vitro

GATA-1 is a zinc finger TF encoded by the GATA-1 gene located on the short-arm of the X-chromosome. Most of GATA-1 mutations were located in exon2 or 3. We describe a male infant presented with dyserythropoietic anemia, who is harbored a novel GG deletion of exon6 in GATA-1 gene and varified its disrupted function in vitro. We confirmed that: (1) by using an unique GATA-1 antibody, which corresponded to amino acids 394-413 of human GATA1, the mutation of the proband led to GATA-1 protein and mRNA defective expressions in both peripheral blood and bone marrow; (2) demonstrated the expression of the GATA-1 mutated form is restricted to erythroblasts and red blood cells, consisted with the proband's abnormal erythropoiesis; (3) temporary transfection of GATA-1-wt(wild type) and GATA-1-indel in Hela cell line, which has no expression of GATA-1 originally, resulted in normal and defective expression both in protein and mRNA leve, respectively; (4) in a manipulated K562 cell line, that its GATA-1 had been knocked down by shRNA, stable transfection GATA-1-indel can not rescue K562 from GATA-1 deficiency.. Our reseach provide new insights into the clinically relevant in vivo function of the C-terminal domain of GATA-1 in human hematopoiesis and the results were validated in two seprerated cell line.