SATB1 regulates SPARC expression in K562 cell line through binding to a specific sequence in the third intron.
Special AT-rich binding protein 1 (SATB1), a cell type-specific nuclear matrix attachment region (MAR) DNA-binding protein, tethers to a specific DNA sequence and regulates gene expression through chromatin remodeling and HDAC (histone deacetylase complex) recruitment. In this study, a SATB1 eukaryotic expression plasmid was transfected into the human erythroleukemia K562 cell line and individual clones that stably over-expressed the SATB1 protein were isolated. Microarray analysis revealed that hundreds of genes were either up- or down-regulated in the SATB1 over-expressing K562 cell lines. One of these was the extra-cellular matrix glycoprotein, SPARC (human secreted protein acidic and rich in cysteine). siRNA knock-down of SATB1 also reduced SPARC expression, which was consistent with elevated SPARC levels in the SATB1 over-expressing cell line. Bioinformatics software Mat-inspector showed that a 17bp DNA sequence in the third intron of SPARC possessed a high potential for SATB1 binding; a finding confirmed by Chromatin immunoprecipitation (ChIP) with anti-SATB1 antibody. Our results show for the first time that forced-expression of SATB1 in K562 cells triggers SPARC up-regulation by binding to a 17bp DNA sequence in the third intron.
Li
K
K
Department of Biochemistry and Molecular Biology, Medical School of Shanghai Jiao Tong University, Shanghai 200025, PR China.
Cai
R
R
Dai
B B
BB
Zhang
X Q
XQ
Wang
H J
HJ
Ge
S F
SF
Xu
W R
WR
Lu
J
J
D001483:Base Sequence; D001665:Binding Sites; D015153:Blotting, Western; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D047369:Chromatin Immunoprecipitation; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007438:Introns / Q000235:genetics*; D020014:K562 Cells; D036961:Matrix Attachment Region Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D020411:Oligonucleotide Array Sequence Analysis; D011485:Protein Binding; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection
D002352:Carrier Proteins; D036961:Matrix Attachment Region Binding Proteins; C076189:SATB1 protein, human