NF45/ILF2 tissue expression, promoter analysis, and interleukin-2 transactivating function

• Published in: Experimental cell research 2005-05, Vol.305 (2), p.312-323
• Main Authors: Zhao, Guohua, Shi, Lingfang, Qiu, Daoming, Hu, Hong, Kao, Peter N.
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; Amino Acid Sequence; Animals; Antigen receptor response element; ANTIGENS; Base Sequence; BRAIN; Cell Line; CHROMOSOMES; DNA; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; DNA-Binding Proteins - physiology; Female; FLUORESCENCE; GENES; Humans; IN-SITU HYBRIDIZATION; Interleukin-2 - genetics; KIDNEYS; LEUKEMIA; LUCIFERASE; LYMPHOMAS; Male; MICE; Molecular Sequence Data; NFATC Transcription Factors; Nuclear Factor 45 Protein; Nuclear Factor 90 Proteins; Nuclear factor of activated T-cells; Nuclear Proteins - genetics; Nuclear Proteins - metabolism; Nuclear Proteins - physiology; PLASMIDS; Promoter Regions, Genetic; PROMOTERS; RECEPTORS; RNA; RNA-binding protein; Tissue Distribution; TRANSCRIPTION; Transcription Factors - genetics; Transcription Factors - metabolism; Transcription Factors - physiology; Transcriptional Activation - genetics; Transcriptional Activation - physiology; Transcriptional activator; VALINE
• ISSN: 0014-4827; 1090-2422
• DOI: 10.1016/j.yexcr.2004.12.030

NF45/ILF2 associates with NF90/ILF3 in the nucleus and regulates IL-2 gene transcription at the antigen receptor response element (ARRE)/NF-AT DNA target sequence (P.N. Kao, L. Chen, G. Brock, J. Ng, A.J. Smith, B. Corthésy, J. Biol. Chem. 269 (1994) 20691–20699). NF45 is widely expressed in normal tissues, especially testis, brain, and kidney, with a predominantly nuclear distribution. NF45 mRNA expression is increased in lymphoma and leukemia cell lines. The human and murine NF45 proteins differ only by substitution of valine by isoleucine at amino acid 142. Fluorescence in situ hybridization localized the human NF45 gene to chromosome 1q21.3, and mouse NF45 gene to chromosome 3F1. Promoter analysis of 2.5 kB of the murine NF45 gene reveals that significant activation is conferred by factors, possible including NF-Y, that bind to the CCAAT-box sequence. The function of human NF45 in regulating IL-2 gene expression was characterized in Jurkat T-cells stably transfected with plasmids directing expression of NF45 cDNA in sense or antisense orientations. NF45 sense expression increased IL-2 luciferase reporter gene activity 120-fold, and IL-2 protein expression 2-fold compared to control cells. NF45 is a highly conserved, regulated transcriptional activator, and one target gene is IL-2.