Pre-TCR signaling components trigger transcriptional activation of a rearranged TCR alpha gene locus and silencing of the pre-TCR alpha locus: implications for intrathymic differentiation - PubMed (original) (raw)

Pre-TCR signaling components trigger transcriptional activation of a rearranged TCR alpha gene locus and silencing of the pre-TCR alpha locus: implications for intrathymic differentiation

S Koyasu et al. Int Immunol. 1997 Oct.

Abstract

A rearranged TCR alpha transgene remains transcriptionally inactive in rag-2-/- thymocytes but can be induced by CD3-mediated signals with concomitant maturation of double-negative (DN) thymocytes to the CD4+CD8+ double-positive (DP) stage. Reciprocally, the same signals silence pre-TCR alpha (pT alpha) expression. In normal C57BL/6 thymocytes, TCR alpha expression is not detected in DN thymocytes while, in contrast, TCR beta expression is initiated at the most immature c-kit+CD44+CD25- stage and continues throughout thymocyte development. pT alpha expression is first detected at the intermediate c-kit +/- CD44+CD25+ DN stage, increases during transition to the more mature c-kit-CD44-CD25+ stage and is lost at the DP stage. Thus, although TCR beta and pT alpha expression are independent, the pre-TCR complex mediates signals controlling the appearance of alpha beta TCR through selective regulation of TCR alpha and pT alpha genes.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources