The Transcription Factor GABP Is a Critical Regulator of B Lymphocyte Development

Laboratory of Molecular Immunology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-1674, USA.
Immunity (Impact Factor: 19.75). 05/2007; 26(4):421-31. DOI: 10.1016/j.immuni.2007.03.010
Source: PubMed

ABSTRACT GA binding protein (GABP) is a ubiquitously expressed Ets-family transcription factor that critically regulates the expression of the interleukin-7 receptor alpha chain (IL-7Ralpha) in T cells, whereas it is dispensable for IL-7Ralpha expression in fetal liver B cells. Here we showed that deficiency of GABPalpha, the DNA-binding subunit of GABP, resulted in profoundly defective B cell development and a compromised humoral immune response, in addition to thymic developmental defects. Furthermore, the expression of Pax5 and Pax5 target genes such as Cd79a was greatly diminished in GABPalpha-deficient B cell progenitors, pro-B, and mature B cells. GABP could bind to the regulatory regions of Pax5 and Cd79a in vivo. Thus, GABP is a key regulator of B cell development, maturation, and function.

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Available from: Xuefang Jing, Mar 19, 2014
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