Regulation of Th2 differentiation and Il4 locus accessibility.
Helper T cells coordinate immune responses through the production of cytokines. Th2 cells express the closely linked Il4, Il13, and Il5 cytokine genes, whereas these same genes are silenced in the Th1 lineage. The Th1/Th2 lineage choice has become a textbook example for the regulation of cell differentiation, and recent discoveries have further refined and expanded our understanding of how Th2 differentiation is initiated and reinforced by signals from antigen-presenting cells and cytokine-driven feedback loops. Epigenetic changes that stabilize the active or silent state of the Il4 locus in differentiating helper T cells have been a major focus of recent research. Overall, the field is progressing toward an integrated model of the signaling and transcription factor networks, cis-regulatory elements, epigenetic modifications, and RNA interference mechanisms that converge to determine the lineage fate and gene expression patterns of differentiating helper T cells.
Harvard Medical School, CBR Institute for Biomedical Research, Boston, Massachusetts 02115, USA. ansel@cbr.med.harvard.edu
K Mark
KM
Ansel
Ivana
I
Djuretic
Bogdan
B
Tanasa
Anjana
A
Rao
D000818:Animals; D002454:Cell Differentiation; D042002:Chromatin Assembly and Disassembly; D016207:Cytokines / Q000235:genetics; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005246:Feedback; D018507:Gene Expression Regulation, Developmental; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007156:Immunologic Memory; D015847:Interleukin-4 / Q000235:genetics*; D051379:Mice; D008957:Models, Genetic; D018448:Models, Immunological; D051880:Receptors, Notch / Q000276:immunology; D015398:Signal Transduction; D018417:Th1 Cells / Q000166:cytology / Q000276:immunology; D018418:Th2 Cells / Q000166:cytology* / Q000276:immunology*
D016207:Cytokines; D006657:Histones; D051880:Receptors, Notch; D015847:Interleukin-4