Yin-Yang 1 and Yin-Yang 2 exert opposing effects on the promoter activity of interleukin 4.
Interleukin (IL)-4 acts on T cells as a growth and activation factor, and promotes the differentiation of type 2 T helper cells. In T cells, expression of the gene encoding IL-4 is regulated by inducible or constitutive factors. Yin-Yang (YY)-1 is one of constitutive transcription factors binding to the IL-4 promoter. The recently identified YY2 protein is similar to YY1, with both sharing high levels of homology in their zinc finger motifs. However, the role of YY2 in T cells is unclear. YY1 and YY2 were constitutively expressed in EL4 T cells, and their expression was not dependent on stimulation. IL-4 promoter (-741/+56 fragment) activity was enhanced by YY1, but inhibited by YY2. The enhanced IL-4 promoter activity by YY1 was reduced by simultaneous expression of YY2. In addition, the DNA binding affinity of YY1 to the IL-4 promoter was adversely affected by YY2. Our results suggest that YY1 and YY2 exert opposing effects on the IL-4 promoter as they compete for the same DNA binding sites.
College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju, Republic of Korea.
Sung Ho
SH
Lee
College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea.
Young-Chang
YC
Cho
College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju, Republic of Korea.
Hyung Min
HM
Jeong
Department of Food and Nutrition, Mokpo National University, Muan, Jeonnam, Republic of Korea.
Kyung Hee
KH
Kim
College of Pharmacy, CHA University, Seongnam, Gyeonggi, Republic of Korea.
Hyun Jin
HJ
Choi
College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju, Republic of Korea. kwanglee@chonnam.ac.kr.
Kwang Youl
KY
Lee
College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju, Republic of Korea. bykang@chonnam.ac.kr.
Bok Yun
BY
Kang
D000818:Animals; D015153:Blotting, Western; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D015847:Interleukin-4 / Q000235:genetics* / Q000378:metabolism; D049409:Luciferases, Firefly / Q000235:genetics; D051379:Mice; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D050986:YY1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D016335:Zinc Fingers / Q000235:genetics
D004268:DNA-Binding Proteins; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C509847:YY2 protein, mouse; C494699:Yy1 protein, mouse; D015847:Interleukin-4; D049409:Luciferases, Firefly
Constitutive factor; IL-4; Th2 cell; YY1; YY2