Significant delay of CML development with Ubp43-deficient bone marrow cells in BCR-ABL retroviral transduction/transplantation assay. (A) Percentage of BCR-ABL–expressing cells (EGFP⁺) in peripheral blood of mice with Mig-p210–transduced and transplanted bone marrow cells. Each color represents the result from one individual mouse. BCR/ABL was expressed in either wild-type Ubp43^+/+ or Ubp43^−/− bone marrow cells (triangles). (B) Ubp43 is clearly detectable in the spleen of mice that develop the CML-like disease. RNA was prepared from the spleen of a mouse that received a transplant of MigR1-transduced Ubp43^+/+ bone marrow cells (control) and the spleen of a mouse with CML-like disease after transplantation with Mig-p210–infected wild-type bone marrow cells (CML). Northern blot was performed with ³²P-labeled Ubp43 cDNA. Ethidium bromide–stained 28S rRNA is shown for relative RNA loading. (C) Kaplan-Meier survival curve of mice that received a transplant of Mig-p210– or MigR1-transduced Ubp43^+/+, Ubp43^+/−, and Ubp43^−/− bone marrow cells. The result is summarized from 3 separate sets of transplantation experiments. (D) Average WBC counts of MigR1- or Mig-p210–transduced Ubp43^+/+ and Ubp43^−/− bone marrow cell recipients.