Identification of LKLF-regulated genes in quiescent CD4+ T lymphocytes.
The transcription factor LKLF (lung Krüppel-like factor) is expressed at high levels in quiescent CD4+ and CD8+ T lymphocytes and provides an important role in establishment and maintenance of the quiescent state. To identify LKLF-regulated genes, we performed microarray analysis using an established Jurkat T cell line containing a tetracycline-inducible LKLF. LKLF induction in this Jurkat T cell line generates a quiescent phenotype that resembles memory CD4+ T lymphocytes. We found that LKLF induction in Jurkat cells resulted in up-regulation (>1.5-fold) of about 100 mRNAs, while it repressed (>1.5-fold) a similar number of mRNAs. A striking feature of the LKLF-stimulated mRNAs was that a significant number of them encode cell surface proteins or proteins implicated in initiating and propagating cellular signaling cascades. The data suggests that LKLF may establish a phenotype that primes quiescent cells for responses to specific extracellular stimuli. The mRNAs encoding CDw52, IL-10R alpha and paxillin were among the most highly induced transcripts in Jurkat T cells, and we observed that the encoded proteins are down-regulated following activation of quiescent CD4+ T cells isolated from healthy blood donors. We also examined whether LKLF-induced quiescence in Jurkat cells could silence transcription of integrated HIV-1 proviruses. We found however that LKLF-induced quiescence is not sufficient to repress expression of HIV-1 proviruses in Jurkat T cells, suggesting that the HIV-1 provirus is resistant to LKLF-regulated quiescence.
Haaland
Richard E
RE
Department of Molecular Virology and Microbiology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
Yu
Wendong
W
Rice
Andrew P
AP
D015703:Antigens, CD / Q000235:genetics; D000951:Antigens, Neoplasm / Q000235:genetics; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D000074301:CD52 Antigen; D003598:Cytoskeletal Proteins / Q000235:genetics; D004247:DNA / Q000235:genetics; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000235:genetics; D016325:HIV Long Terminal Repeat; D006801:Humans; D066298:In Vitro Techniques; D019169:Jurkat Cells; D051741:Kruppel-Like Transcription Factors; D020411:Oligonucleotide Array Sequence Analysis; D051419:Paxillin; D010750:Phosphoproteins / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D018123:Receptors, Interleukin / Q000235:genetics; D053701:Receptors, Interleukin-10; D016192:Resting Phase, Cell Cycle; D015534:Trans-Activators / Q000378:metabolism*
D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000074301:CD52 Antigen; C000613862:CD52 protein, human; D003598:Cytoskeletal Proteins; D006023:Glycoproteins; C096161:KLF2 protein, human; D051741:Kruppel-Like Transcription Factors; C496061:PXN protein, human; D051419:Paxillin; D010750:Phosphoproteins; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053701:Receptors, Interleukin-10; D015534:Trans-Activators; D004247:DNA