Splenomegaly and Modified Erythropoiesis in KLF13–/– Mice

To study the function of the Krüppel-like transcription factor KLF13 in vivo , we generated mice with a disrupted Klf13 allele. Although Klf13 – / – mice are viable, fewer mice were present at 3 weeks than predicted by Mendelian inheritance. Viable Klf13 – / – mice had reduced numbers of circulating erythrocytes and a larger spleen. The spleen contained an increased number of Ter119 med CD71 hi , Ter119 hi CD71 hi , and Ter119 hi CD71 med cells but not Ter119 hi CD71 – cells, indicating an increase in less mature erythroblasts. A higher proportion of the Ter119 med CD71 hi cells were proliferating, indicating that the mice were under a degree of erythropoietic stress. These data indicate that KLF13 is involved in the normal control of erythropoiesis.