Precise developmental regulation of Ets family transcription factors during specification and commitment to the T cell lineage.
Ets family transcription factors control the expression of a large number of genes in hematopoietic cells. Here we show strikingly precise differential expression of a subset of these genes marking critical, early stages of mouse lymphocyte cell-type specification. Initially, the Ets family member factor Erg was identified during an arrayed cDNA library screen for genes encoding transcription factors expressed specifically during T cell lineage commitment. Multiparameter fluorescence-activated cell sorting for over a dozen cell surface markers was used to isolate 18 distinct primary-cell populations representing discrete T cell and B cell developmental stages, pluripotent lymphoid precursors, immature NK-like cells and myeloid hematopoietic cells. These populations were monitored for mRNA expression of the Erg, Ets-1, Ets-2, Fli-1, Tel, Elf-1, GABPalpha, PU.1 and Spi-B genes. The earliest stages in T cell differentiation show particularly dynamic Ets family gene regulation, with sharp transitions in expression correlating with specification and commitment events. Ets, Spi-B and PU.1 are expressed in these stages but not by later T-lineage cells. Erg is induced during T-lineage specification and then silenced permanently, after commitment, at the beta-selection checkpoint. Spi-B is transiently upregulated during commitment and then silenced at the same stage as Erg. T-lineage commitment itself is marked by repression of PU.1, a factor that regulates B-cell and myeloid genes. These results show that the set of Ets factors mobilized during T-lineage specification and commitment is different from the set that maintains T cell gene expression during thymocyte repertoire selection and in all classes of mature T cells.
Anderson
M K
MK
Stowers Institute for Medical Research, Kansas City, MO 64110, USA. evroth@its.caltech.edu
Hernandez-Hoyos
G
G
Diamond
R A
RA
Rothenberg
E V
EV
D000818:Animals; D001402:B-Lymphocytes / Q000502:physiology; D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins / Q000235:genetics; D000072237:ERG1 Potassium Channel; D051638:Ether-A-Go-Go Potassium Channels; D018507:Gene Expression Regulation, Developmental; D005821:Genetic Techniques; D017403:In Situ Hybridization / Q000379:methods; D007694:Killer Cells, Natural / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D009687:Nuclear Proteins; D015221:Potassium Channels / Q000235:genetics; D024642:Potassium Channels, Voltage-Gated; D050784:Proto-Oncogene Protein c-ets-1; D050787:Proto-Oncogene Protein c-ets-2; D051789:Proto-Oncogene Protein c-fli-1; D011518:Proto-Oncogene Proteins / Q000235:genetics; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013234:Stem Cells / Q000502:physiology*; D013601:T-Lymphocytes / Q000502:physiology*; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D000097764:ETS Translocation Variant 6 Protein; D000099232:Proto-Oncogene Protein Spi-1
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D000072237:ERG1 Potassium Channel; D051638:Ether-A-Go-Go Potassium Channels; D009687:Nuclear Proteins; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D050784:Proto-Oncogene Protein c-ets-1; D050787:Proto-Oncogene Protein c-ets-2; D051789:Proto-Oncogene Protein c-fli-1; D011518:Proto-Oncogene Proteins; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000097764:ETS Translocation Variant 6 Protein; D000099232:Proto-Oncogene Protein Spi-1; C512897:ELF1 protein, human; C107465:ERF protein, human; C494041:ETS1 protein, human; C512896:Elf1 protein, mouse; C494042:Ets1 protein, mouse; C494070:Ets2 protein, mouse; C497426:Fli1 protein, mouse; C000606915:Kcnh2 protein, mouse; C489532:Tcf12 protein, mouse; C073366:TCF12 protein, human; C076877:SPIB protein, human