Selectively impaired development of intestinal T cell receptor gamma delta+ cells and liver CD4+ NK1+ T cell receptor alpha beta+ cells in T cell factor-1-deficient miceThe winged-helix transcription factor Trident is expressed in actively dividing lymphocytesAn HMG box containing T-cell factor required for thymocyte differentiationCritical involvement of Tcf-1 in expansion of thymocytesHigh expression of the HMG box factor sox-13 in arterial walls during embryonic development