Identification of important regulatory region of Th-POK.
CD4(+) and CD8(+) T cells develop from CD4(+)CD8(+) thymocytes. Although it has been reported that expression of the transcription factor Th-POK is important for CD4(+) T cell development, the detailed mechanism regulating Th-POK expression is still obscure. By comparing the promoter regions of the Th-POK gene between human and mouse, I found that the region 3600 base pairs (bps) upstream from the transcription initiation site of the Th-POK gene was highly conserved. To identify the important element(s) regulating Th-POK expression in CD4(+) T cells, I investigated the promoter activity of this region using a luciferase assay in the human T cell line Jurkat. I identified a positive regulatory element in this region 22 bps in length located 600 bp upstream from the transcription initiation site. This 22 bp element had a consensus binding sequence for SAP-1, which is encoded by the Elk4 gene and is activated by the Erk pathway. These data suggest that the 22 bp element might positively regulate Th-POK expression through Erk-SAP-1 signaling.
Shamsul Alam
Muhammad
M
Department of Immunology and Parasitology, Institute of Health Biosciences, the University of Tokushima Graduate School, Tokushima, Japan.
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000235:genetics*; D006801:Humans; D019169:Jurkat Cells; D020935:MAP Kinase Signaling System; D051379:Mice; D016254:Mutagenesis, Insertional; D011401:Promoter Regions, Genetic; D012045:Regulatory Sequences, Nucleic Acid; D017384:Sequence Deletion; D015398:Signal Transduction; D013045:Species Specificity; D014157:Transcription Factors / Q000235:genetics*; D024363:Transcription Initiation Site; D050808:ets-Domain Protein Elk-4 / Q000378:metabolism
D004268:DNA-Binding Proteins; D014157:Transcription Factors; D050808:ets-Domain Protein Elk-4; C494193:ELK4 protein, human; C497211:Zbtb7b protein, mouse; C484225:ZBTB7B protein, human