Molecular regulation of MHC class I chain-related protein A expression after HDAC-inhibitor treatment of Jurkat T cells.
In this study, we characterize the molecular signal pathways that lead to MHC class I chain-related protein A (MICA) expression after histone deacetylase (HDAC)-inhibitor (HDAC-i) treatment of Jurkat T cells. Chelating calcium with BAPTA-AM or EGTA potently inhibited HDAC- and CMV-mediated MICA/B expression. It was further observed that endoplasmic reticulum calcium stores were depleted after HDAC treatment. NF-kappaB activity can be induced by HDAC treatment. However, nuclear translocation of NF-kappaB p65 was not observed after HDAC treatment of Jurkat T cells and even though we could effectively inhibit p65 expression by siRNA, it did not modify MICA/B expression. To identify important elements in MICA regulation, we made a promoter construct consisting of approximately 3 kb of the proximal MICA promoter in front of GFP. Deletion analysis showed that a germinal center-box containing a putative Sp1 site from position -113 to -93 relative to the mRNA start site was important for HDAC and CMV-induced promoter activity. Sp1 was subsequently shown to be important, as targeted mutation of the Sp1 binding sequence or siRNA mediated down modulation of Sp1-inhibited MICA promoter activity and surface-expression.
Andresen
Lars
L
Department of Immunology, Institute of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
Jensen
Helle
H
Pedersen
Marianne T
MT
Hansen
Karen A
KA
Skov
Søren
S
D021581:Active Transport, Cell Nucleus; D002118:Calcium / Q000037:antagonists & inhibitors / Q000378:metabolism; D002614:Chelating Agents / Q000494:pharmacology; D003587:Cytomegalovirus / Q000235:genetics; D047630:Depsipeptides / Q000494:pharmacology; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation; D015395:Histocompatibility Antigens Class I / Q000235:genetics* / Q000378:metabolism; D056572:Histone Deacetylase Inhibitors; D006801:Humans; D019169:Jurkat Cells; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000235:genetics; D016329:Sp1 Transcription Factor / Q000378:metabolism; D013601:T-Lymphocytes / Q000201:enzymology / Q000276:immunology*; D051996:Transcription Factor RelA / Q000378:metabolism
D002614:Chelating Agents; D047630:Depsipeptides; D004791:Enzyme Inhibitors; D015395:Histocompatibility Antigens Class I; D056572:Histone Deacetylase Inhibitors; C099187:MHC class I-related chain A; C098080:MICB antigen; D034741:RNA, Small Interfering; D016329:Sp1 Transcription Factor; D051996:Transcription Factor RelA; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D004533:Egtazic Acid; C087123:romidepsin; D002118:Calcium