A Change in the Structure of V Chromatin Associated with TCR Allelic Exclusion
نویسندگان
چکیده
منابع مشابه
Biochemical and functional analyses of chromatin changes at the TCR-beta gene locus during CD4-CD8- to CD4+CD8+ thymocyte differentiation.
Allelic exclusion is the process wherein lymphocytes express Ag receptors from only one of two possible alleles, and is effected through a feedback inhibition of further rearrangement of the second allele. The feedback signal is thought to cause chromatin changes that block accessibility of the second allele to the recombinase. To identify the putative chromatin changes associated with allelic ...
متن کاملRegulation of TCRβ allelic exclusion by gene segment proximity and accessibility.
Ag receptor loci are regulated to promote allelic exclusion, but the mechanisms are not well understood. Assembly of a functional TCR β-chain gene triggers feedback inhibition of V(β)-to-DJ(β) recombination in double-positive (DP) thymocytes, which correlates with reduced V(β) chromatin accessibility and a locus conformational change that separates V(β) from DJ(β) gene segments. We previously g...
متن کاملThe Requirement for Pre-TCR during Thymic Differentiation Enforces a Developmental Pause That Is Essential for V-DJβ Rearrangement
T cell development occurs in the thymus and is critically dependent on productive TCRβ rearrangement and pre-TCR expression in DN3 cells. The requirement for pre-TCR expression results in the arrest of thymocytes at the DN3 stage (β checkpoint), which is uniquely permissive for V-DJβ recombination; only cells expressing pre-TCR survive and develop beyond the DN3 stage. In addition, the requirem...
متن کاملThe CD3-γδε and CD3-ζ/η Modules Are Each Essential for Allelic Exclusion at the T Cell Receptor β Locus but Are Both Dispensable for the Initiation of V to (D)J Recombination at the T Cell Receptor–β, –γ, and –δ Loci
The pre-T cell receptor (TCR) associates with CD3-transducing subunits and triggers the selective expansion and maturation of T cell precursors expressing a TCR-beta chain. Recent experiments in pre-Talpha chain-deficient mice have suggested that the pre-TCR may not be required for signaling allelic exclusion at the TCR-beta locus. Using CD3-epsilon- and CD3-zeta/eta-deficient mice harboring a ...
متن کاملTCR Feedback Signals Inhibit the Coupling of Recombinationally Accessible V14 Segments with DJ Complexes
Antigen receptor allelic exclusion is thought to occur through mono-allelic initiation and subsequent feedback inhibition of recombinational accessibility. However, our previous analysis of mice containing a V(D)J recombination reporter inserted into Vβ14 (Vβ14Rep) indicated that Vβ14 chromatin accessibility is bi-allelic. To determine whether Vβ14 recombinational accessibility is subject to fe...
متن کامل