Abstract
Animal models of erythropoiesis related genes have been limited by the fact that some of these genes have non-erythroid expression and other functions in addition to erythropoiesis and thus their knock-out may be embryonic lethal. Tissue specific knock-out or knock-in mice models employing GATA-1-Cre and other constructs showed that these promoters are also active in non-hematopoietic tissues, i.e. GATA-1 has activity in early embryonic development and in neuronal tissue.
Suzuki et al (Blood, 2002, 100; 2279
) isolated the GATA-1 locus hematopoietic regulatory domain (GATA-1-HRD) and demonstrated that the expression of a transgene under its control is limited to the hematopoietic tissue. We generated a transgenic mouse expressing an improved Cre (iCre) under GATA-1-HRD promoter control. This mouse was crossbred with ROSA 26 mouse and the progeny was examined for tissue specificity of iCre expression using beta-galactosidase staining. Brain, spleen, kidney, heart, thymus, liver, lung and ovary were examined for whole organ LacZ staining. All tested organs were negative except kidney and spleen where some positivity was observed. Subsequently, we prepared tissue sections from kidney, spleen and bone marrow and stained with LacZ and anti-beta-galactosidase antibody. Only the bone marrow EpoR expressing cells were positive; the kidney and the spleen cells were negative. Although Suzuki et al previously showed expression of the GATA-1-HRD driven erythropoietin receptor in spleen using RT-PCR, we were not able to find iCre expression in the splenic cells using these approaches. We demonstrate that our transgenic mouse (GATA-1-HRD-iCre) showed a restricted iCre expression in hematopoietic tissue that differs from previous studies of other hematopoiesis specific cre mouse. We conclude that this mouse model should be useful in studies of function of erythroid specific genes.Disclosure: No relevant conflicts of interest to declare.
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2006, The American Society of Hematology
2006
