GATA3 and the T-cell lineage: essential functions before and after T-helper-2-cell differentiation

The transcription factor GATA-binding protein 3 (GATA3) is best known as a master regulator of T-helper-2-cell differentiation. However, as part of a network of other transcription factors, GATA3 is also important in determining cell fate at earlier stages of haematopoiesis and lymphoid-cell development. Many advances in our understanding of the molecules that regulate the development, differentiation and function of T cells have been made over the past few years. One important regulator of T-cell differentiation is the transcription factor GATA-binding protein 3 (GATA3). Although the main function of GATA3 is to act as a master transcription factor for the differentiation of T helper 2 (TH2) cells, new research has helped to uncover crucial functions of GATA3 in T cells that go beyond TH2-cell differentiation and that are important at earlier stages of haematopoietic and lymphoid-cell development. This Review focuses on the functions of GATA3 from early thymocyte development to effector T-cell differentiation. In addition, we discuss the interactions between GATA3 and other transcription factors and signalling pathways, and highlight the functional significance of the GATA3 protein structure.