DNA-binding domain of T-box transcription factor T, T-box transcription factor 19 and related T-box proteins
Tbx19 (also known as Tpit) is a T-box factor restricted to two pituitary (pro-opiomelanocortin) POMC-expressing lineages, the corticotrophs and melanotrophs; it controls terminal differentiation of these lineages. TBX19 activates POMC gene transcription with the cooperation of another transcription factor Pitx1. TBXT, also known as Brachyury protein, or protein T, is a transcription factor needed for posterior mesoderm formation and differentiation as well as for the notochord development during embryogenesis. It binds to a 24 base-pair (bp) palindromic site (called the T site) and activates gene transcription when bound to such a site. This subfamily belongs to the T-box family of transcription factors which play a multitude of diverse functions throughout development. TBXT is the founding member of the T-box family, members of which share a conserved DNA-binding domain (T-box) which binds DNA in a sequence-specific manner. Common features shared by T-box family members are DNA-binding and transcriptional regulatory activity, a role in development, and conserved expression patterns.