Date of Award


Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)




Susan Hunter

Second Committee Member

Luanne Peters

Third Committee Member

John Singer


Two erythroid-specific Cre-expressing transgenic mouse strains were established. In the first, expression of Cre recombinase was driven under the control of the Ael promoter. Three founder lines were obtained following pronuclear injection of the construct, and maintained on a C57BL/ 6J background at the Jackson Laboratory. Two of the founder lines had a transgene copy number of two, and the third line had a copy number of three. Cre recombinase expression was detected in reticulocytes and phenylhydrazine treated spleens of all three lines by RT-PCR. Protein detection was attempted by staining tissues with an anti-Cre recombinase antibody with mixed results. In addition, transgenic mice were mated to a reporter strain of mice (ROSA); the resulting offspring showed no Cre recombinase expression in the erythroid tissues of adult spleen or bone marrow or in fetal livers from 12 day or 14 day embryos. Therefore it is postulated that Cre recombinase expression in the AEl-cre transgenic mice is turned on late during erythopoietic development and is not expressed at detectable levels prior to the reticulocyte stage. In the second transgenic strain, Cre was driven by the beta-globin promoter. Seven founder lines were created, genotyped and maintained. This project was in collaboration with Dr. Kenneth Peterson (KUMC) to recreate a strain that was lost. The original lines expressed Cre in erythroid cells and, surprisingly, in megakaryocytes. In the new transgenic lines Cre is expressed in erythroid lineages only; cre is not expressed in megakaryocytes.