title: Dynamic repositioning of CD4 and CD8 genes during T cell development.
abstract: Although stable repression of CD4 and CD8 genes is a central feature of T cell lineage commitment, we lack detailed information about the timing and mechanism of this repression. Stable gene repression has been linked to the position of genes within the nucleus. Therefore, information about the nuclear position of CD4 and CD8 genes during T cell development could provide insights into both the mechanism of regulation of CD4 and CD8 genes, and the process of lineage commitment. Here, we report that lineage-specific repression of CD4 and CD8 genes is associated with the repositioning of alleles close to heterochromatin. We also provide evidence that the relocalization of CD4 and CD8 genes to heterochromatin can occur as an early response to positive selection signals. We discuss our results in terms of our current knowledge of CD4 and CD8 gene regulation and CD4 versus CD8 lineage commitment.
authors.affiliation: Department of Molecular and Cell Biology, 475 Life Science Additions, University of California, Berkeley, Berkeley, CA 94720, USA.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Delaire
authors.forename: Yina Hsing
authors.initials: YH
authors.lastname: Huang
authors.forename: Shaio Wei
authors.initials: SW
authors.lastname: Chan
authors.forename: Ellen A
authors.initials: EA
authors.lastname: Robey
mesh_terms: D000818:Animals; D015704:CD4 Antigens / Q000032:analysis / Q000235:genetics*; D016827:CD8 Antigens / Q000032:analysis / Q000235:genetics*; D019070:Cell Lineage; D002874:Chromosome Mapping; D006570:Heterochromatin / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D012333:RNA, Messenger / Q000032:analysis; D011948:Receptors, Antigen, T-Cell / Q000502:physiology; D013601:T-Lymphocytes / Q000502:physiology*
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens; D006570:Heterochromatin; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell