title: Abundant expression of erythroid transcription factor P45 NF-E2 mRNA in human peripheral granurocytes.
abstract: Transcription factor NF-E2 is crucial for regulation of erythroid-specific gene expression. p45 subunit of NF-E2 contains a basic-leucine zipper domain and dimerizes with the small Maf family protein to form functional NF-E2 complex. While p45 expression was shown to be restricted to erythroid cells, megakaryocytes and mast cells in hematopoietic lineage, we found in this study that p45 mRNA is abundantly transcribed in the granulocyte fraction of human peripheral blood cells. As neutrophils occupy approximately 92% of the cells in granulocyte fraction of human peripheral blood cells. As neutrophils occupy approximately 92% of the cells in this fraction, the cells expressing p45 is most likely to be neutrophils. p45 mRNA is also expressed in HL-60 promyelocytes, albeit the expression level is much lower than that of the granulocyte fraction. HL-60 cells were found to express mafK mRNA, indicating the presence of genuine NF-E2 complex in the cells. Although p45 mRNA is transcribed from two different promoters, aNF-E2 promoter and fNF-E2 promoter, in erythroid and megakaryocytic lineage cells, p45 mRNA is transcribed only from aNF-E2 promoter. The expression of p45 megakaryocytic lineage cells, p45 mRNA is transcribed only from aNF-E2 promoter. The expression of p45 mRNA in the neutrophils declined rapidly after transfer of the cells to in vitro culture and G-CSF could not sustain the expression from the down-regulation, suggesting the E2 may also participate in the regulation of neutrophil-specific gene expression.
authors.affiliation: Department of Pediatrics, Hirosaki University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Toki
authors.forename: J
authors.initials: J
authors.lastname: Itoh
authors.forename: K
authors.initials: K
authors.lastname: Arai
authors.forename: J
authors.initials: J
authors.lastname: Kitazawa
authors.forename: M
authors.initials: M
authors.lastname: Yokoyama
authors.forename: K
authors.initials: K
authors.lastname: Igarashi
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.forename: E
authors.initials: E
authors.lastname: Ito
mesh_terms: D017398:Alternative Splicing; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D050981:Erythroid-Specific DNA-Binding Factors; D015870:Gene Expression / Q000187:drug effects; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D006098:Granulocytes / Q000378:metabolism*; D018922:HL-60 Cells; D006801:Humans; D050985:MafK Transcription Factor; D008533:Megakaryocytes; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000097:blood; D014157:Transcription Factors / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D016335:Zinc Fingers
chemical_list: D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; C494695:MAFK protein, human; D050985:MafK Transcription Factor; D050983:NF-E2 Transcription Factor; D050984:NF-E2 Transcription Factor, p45 Subunit; C494692:NFE2 protein, human; D012333:RNA, Messenger; D014157:Transcription Factors; D016179:Granulocyte Colony-Stimulating Factor