Fig 1.
A) DNA sequence of proband and parents showing a single base pair change from G in the parents to a T in the proband at nucleotide position c.1428+1 G>T. B) Diagram of the GATA6 protein containing a GATA family homeodomain and two DNA binding zinc fingers. Arrows indicate locations of GATA6 variants discovered in proband 1 and 2.
Fig 2.
DNA Sanger sequencing of proband 2 demonstrates he has a normal allele (upper) and a mutant allele (lower). The wild-type GATA6 sequence c964_970 (underlined region) is deleted in the mutant allele (arrow).
Fig 3.
Loss of Hnf4α promoter activation by GATA6 with GATA6Y323fsX21.
A) Human wild-type GATA6 and/or GATA6Y323fsX21 labeled ‘GATA6 variant’ were co-expressed with Hnf4α promoter in INS-1 cells. Hnf4α promoter luciferase activity was measured and levels normalized to vector alone. *P = 0.00001. B) Western blot analysis of human GATA6 protein (W lane) and GATA6Y323fsX21 (M lane) expressed in HEK 293T cells. Vector (V lane) only was a negative control and to approximate the size a protein ladder (L lane) was utilized. GATA6 was detected with a GATA6 antibody against the N-terminal of the protein and beta actin was measured as a loading control.