Library Subscription: Guest
Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections
Critical Reviews™ in Immunology
IF: 1.352 5-Year IF: 3.347 SJR: 0.657 SNIP: 0.55 CiteScore™: 2.19

ISSN Print: 1040-8401
ISSN Online: 2162-6472

Volumes:
Volume 39, 2019 Volume 38, 2018 Volume 37, 2017 Volume 36, 2016 Volume 35, 2015 Volume 34, 2014 Volume 33, 2013 Volume 32, 2012 Volume 31, 2011 Volume 30, 2010 Volume 29, 2009 Volume 28, 2008 Volume 27, 2007 Volume 26, 2006 Volume 25, 2005 Volume 24, 2004 Volume 23, 2003 Volume 22, 2002 Volume 21, 2001 Volume 20, 2000 Volume 19, 1999 Volume 18, 1998 Volume 17, 1997 Volume 16, 1996 Volume 15, 1995 Volume 14, 1994

Critical Reviews™ in Immunology

DOI: 10.1615/CritRevImmunol.v26.i6.10
pages 475-486

Regulation of Thymocyte Survival by Transcriptional Coactivators

Huimin Xie
Department of Microbiology & Immunology, College of Medicine, University of Illinois, Chicago, IL
Zhaofeng Huang
Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080 P.R. China
Ruiqing Wang
Division of Immunology, Beckman Research Institute of the City of Hope; Irell & Manella Graduate School of Biological Sciences, City of Hope, Duarte, CA 91010
Zuoming Sun
Department of Microbiology & Immunology, College of Medicine, University of Illinois at Chicago; Division of Immunology, Beckman Research Institute of the City of Hope, Duarte, CA 91010

ABSTRACT

A majority of the developing T cells are eliminated by apoptosis because they do not meet the positive and negative selection criteria. Developing T cells are thus susceptible to apoptotic signals. On the other hand, there are mechanisms to prevent developing T cells from premature apoptosis. Maintenance of a fine balance between life and death is thus critical for successful completion of T-cell development. Our recent studies demonstrated an essential role of transcriptional coactivators in maintaining such a balance for developing T cells. Transcriptional coactivators are recruited by transcriptional factors to quantitatively regulate gene expression via modifying chromatin structure. Two transcriptional factors, TCF-1 and RORγt, are required to upregulate the levels of Bcl-xL, a critical survival factor for CD4+CD8+ double-positive thymocytes. However, TCF-1 and RORγt by themselves are not sufficient to stimulate Bcl-xL expression. Transcriptional coactivator β-catenin recruited by TCF-1, and steroid receptor coactivators (SRCs) recruited by RORγt, are also required for optimal stimulation of Bcl-xL expression. Thus, transcriptional coactivators are a substantial component of the transcriptional machinery to regulate thymocye survival, ensuring the completion of T-cell development.