Suppressive effect of Elf-1 on FcepsilonRI alpha-chain expression in primary mast cells.
The high-affinity receptor for immunoglobulin E (IgE), FcepsilonRI, is specifically expressed in mast cells and basophils and plays a key role in IgE-mediated allergic reactions. The transcription factor Elf-1 has been previously identified to bind to the promoter of the human FcepsilonRI alpha-chain, which is essential for the function and expression of FcepsilonRI. In the present study, Elf-1 siRNA was conducted to evaluate the effects of Elf-1 on FcepsilonRI alpha-chain expression in the primary mouse mast cells, bone marrow-derived mast cells (BMMC). Introduction of Elf-1 siRNA effectively reduced expression levels of Elf-1 mRNA and protein in BMMC. Transient reporter assay showed that the knockdown of Elf-1 by siRNA resulted in increased FcepsilonRI alpha-chain promoter activity, while overexpression of Elf-1 suppressed alpha-chain promoter activity in BMMC. Elf-1 siRNA-treated BMMC exhibited marked upregulation of FcepsilonRI alpha-chain transcription, whereas beta-chain mRNA was not affected by Elf-1 siRNA. Chromatin immunoprecipitation assay showed that the amount of transcription factor PU.1, recognizing the cis-element close to the Elf-1-site on the FcepsilonRI alpha-chain promoter, was significantly increased by introduction of Elf-1 siRNA. These results indicate that Elf-1 negatively regulates FcepsilonRI alpha-chain expression by suppressing PU.1-mediated transcription of the alpha-chain in BMMC.
Wang
Qing-Hui
QH
Atopy Research Center, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
Nishiyama
Chiharu
C
Nakano
Nobuhiro
N
Shimokawa
Naomi
N
Hara
Mutsuko
M
Kanada
Shunsuke
S
Ogawa
Hideoki
H
Okumura
Ko
K
D000818:Animals; D015153:Blotting, Western; D001853:Bone Marrow / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D036383:Ephrin-A2 / Q000037:antagonists & inhibitors*; D005786:Gene Expression Regulation; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008407:Mast Cells / Q000378:metabolism*; D051379:Mice; D011401:Promoter Regions, Genetic / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000494:pharmacology*; D017455:Receptors, IgE / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D015854:Up-Regulation; D000099232:Proto-Oncogene Protein Spi-1
D036383:Ephrin-A2; D008156:Luciferases; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D017455:Receptors, IgE; D015534:Trans-Activators; D000099232:Proto-Oncogene Protein Spi-1; C475664:FCER1A protein, human