The human TBX6 gene: Cloning and assignment to chromosome 16p11.2

Tbx6 is a member of the T-box family of proteins, which share a region of h omology corresponding to the DNA-binding domain of the transcription factor T. Previous expression studies and knockout experiments in mice indicate t hat Tbx6 is important for specification of paraxial mesoderm structures, We have isolated and characterized the human orthologue, TBX6. Sequence compa risons show that overall the nucleotide homology between human and mouse TB X6/Tbx6 is 84%; within the T-box there is 89% nucleotide homology and 96% a mino acid identity. TBX6 maps to chromosome 16 p11.2, a region syntenic wit h mouse chromosome 7, at 61 cM, the map position of mouse Tbx6. RT-PCR stud ies of RNA distribution indicate that this gene is expressed not only durin g gastrulation but has a second phase of expression in some adult tissues i ncluding testis. DNA/protein-binding studies demonstrate that Tbx6 binds to the same target DNA as T protein and can form a dimeric complex with DNA. We could find no evidence that Tbx6 forms a heterodimer with T. (C) 1999 Ac ademic Press.