Sp1-mediated transcription regulation of TAF-Ialpha gene encoding a histone chaperone.
TAF-I, one of histone chaperones, consists of two subtypes, TAF-Ialpha and TAF-Ibeta. The histone chaperone activity of TAF-I is regulated by dimer patterns of these subtypes. TAF-Ibeta is expressed ubiquitously, while the expression level of TAF-Ialpha with less activity than TAF-Ibeta differs among cell types. It is, therefore, assumed that the expression level of TAF-Ialpha in a cell is important for the TAF-I activity level. Here, we found that TAF-Ialpha and TAF-Ibeta genes are under the control of distinct promoters. Reporter assays and gel shift assays demonstrated that Sp1 binds to three regions in the TAF-Ialpha promoter and two or all mutaions of the three Sp1 binding regions reduced the TAF-Ialpha promoter activity. ChIP assays demonstrated that Sp1 binds to the TAF-Ialpha promoter in vivo. Furthermore, the expression level of TAF-Ialpha mRNA was reduced by knockdown of Sp1 using siRNA method. These studies indicated that the TAF-Ialpha promoter is under the control of Sp1.
Asaka
Masamitsu N
MN
Department of Infection Biology, Graduate School of Comprehensive Human Science and Institute of Basic Medical Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan.
Murano
Kensaku
K
Nagata
Kyosuke
K
D000818:Animals; D001483:Base Sequence; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics*; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D056488:Histone Chaperones; D006657:Histones / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000235:genetics; D051379:Mice; D018832:Molecular Chaperones / Q000235:genetics*; D011401:Promoter Regions, Genetic; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D056488:Histone Chaperones; D006657:Histones; D018832:Molecular Chaperones; C513473:SET protein, human; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D008156:Luciferases