Expression of TEF during hematopoiesis. (A) Northern blot analysis of human hematolymphoid tissues. The blot was hybridized with human TEF, DBP, HLF, and β-actin cDNA probes. Lane 1, spleen; lane 2, lymph node; lane 3, thymus; lane 4, peripheral blood leukocyte; lane 5, bone marrow (BM); and lane 6, fetal liver. The mobility of 285 and 185 rRNA was indicated. (B) Patterns of Tef expression in murine myeloid and lymphoid progenitors in different stages of development. cDNA was synthesized from total RNA extracted from 5000 cells of each hematopoietic progenitor subset that had been sorted from bone marrows by FACS (lanes 1-7) as well as unpurified bone marrow mononuclear cells (lane 8). The cDNA was subjected to PCR with primers specific for the murine Tef (top panel) and Hprt (bottom panel) genes. The PCR product of amplification of Tef was subjected to nested PCR (middle panel). HSC indicates hematopoietic stem cells; CMP, common myeloid progenitor; GMP, granulocyte-monocyte progenitor; MEP, megakaryocyte-erythrocyte progenitor; and CLP, common lymphoid progenitor.