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The basic helix-loop-helix transcription factor E2-2 is involved in T lymphocyte development.

I Bergqvist·M Eriksson·J Saarikettu·B Eriksson·B Corneliussen·T Grundström·D Holmberg
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Abstract

E2A, HEB and E2-2 genes encode a group of basic helix-loop-helix (bHLH) transcription factors that are structurally and functionally similar. Deletion of the genes encoding either of these proteins leads to early lethality and a block in B lymphocyte development. Evidence for a function in T lymphocyte development has, however, only been reported for E2A and HEB. To further elucidate the role of E2-2 at developmental stages that have proven difficult to study due to the early lethality phenotype of mice defective in E2-2, we generated and analyzed mice conditionally mutated in the E2-2 gene. These mice are mosaic with respect to E2-2 expression, consisting of cells with either one functional and one null mutated E2-2 allele or two null mutated alleles. Using this experimental model, we find that cells with a homozygous null mutated E2-2 gene are under-represented in B lymphocyte as well as T lymphocyte cell lineages as compared to other hematopoietic or non-hematopoietic cell lineages. Our data suggests that E2-2 deficiency leads to a partial block in both B and T lymphocyte development. The block in T cell development appears to occur at an early stage in differentiation, since skewing in the mosaicism is observed already in CD4+8+ double-positive thymocytes.

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AllelesAnimalsB-LymphocytesBasic Helix-Loop-Helix Leucine Zipper Transcription FactorsCell DifferentiationCell LineageDNA-Binding ProteinsGene TargetingGenotypeHelix-Loop-Helix MotifsHematopoiesisImmunologic Deficiency SyndromesLymphocyte CountLymphocyte SubsetsMiceMice, Inbred C57BLMice, KnockoutMosaicismNerve Tissue ProteinsSpleenT-LymphocytesTCF Transcription FactorsThymus GlandTrans-ActivatorsTranscription Factor 4Transcription FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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I Bergqvist, M Eriksson, J Saarikettu, B Eriksson, B Corneliussen, T Grundström, D Holmberg. 2000. The basic helix-loop-helix transcription factor E2-2 is involved in T lymphocyte development.. https://doi.org/10.1002/1521-4141(200010)30%3A10%3C2857%3A%3Aaid-immu2857%3E3.0.co%3B2-g

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