GATA2 is required for lymphatic vessel valve development and maintenance
Jan Kazenwadel, … , Hamish S. Scott, Natasha L. Harvey
Jan Kazenwadel, … , Hamish S. Scott, Natasha L. Harvey
Published July 27, 2015
Citation Information: J Clin Invest. 2015;125(8):2979-2994. https://doi.org/10.1172/JCI78888.
View: Text | PDF
Research Article Development Vascular biology

GATA2 is required for lymphatic vessel valve development and maintenance

Abstract

Heterozygous germline mutations in the zinc finger transcription factor GATA2 have recently been shown to underlie a range of clinical phenotypes, including Emberger syndrome, a disorder characterized by lymphedema and predisposition to myelodysplastic syndrome/acute myeloid leukemia (MDS/AML). Despite well-defined roles in hematopoiesis, the functions of GATA2 in the lymphatic vasculature and the mechanisms by which GATA2 mutations result in lymphedema have not been characterized. Here, we have provided a molecular explanation for lymphedema predisposition in a subset of patients with germline GATA2 mutations. Specifically, we demonstrated that Emberger-associated GATA2 missense mutations result in complete loss of GATA2 function, with respect to the capacity to regulate the transcription of genes that are important for lymphatic vessel valve development. We identified a putative enhancer element upstream of the key lymphatic transcriptional regulator PROX1 that is bound by GATA2, and the transcription factors FOXC2 and NFATC1. Emberger GATA2 missense mutants had a profoundly reduced capacity to bind this element. Conditional Gata2 deletion in mice revealed that GATA2 is required for both development and maintenance of lymphovenous and lymphatic vessel valves. Together, our data unveil essential roles for GATA2 in the lymphatic vasculature and explain why a select catalogue of human GATA2 mutations results in lymphedema.

Authors

Jan Kazenwadel, Kelly L. Betterman, Chan-Eng Chong, Philippa H. Stokes, Young K. Lee, Genevieve A. Secker, Yan Agalarov, Cansaran Saygili Demir, David M. Lawrence, Drew L. Sutton, Sebastien P. Tabruyn, Naoyuki Miura, Marjo Salminen, Tatiana V. Petrova, Jacqueline M. Matthews, Christopher N. Hahn, Hamish S. Scott, Natasha L. Harvey

×

Figure 2

GATA2 Emberger mutants exhibit reduced DNA-binding affinity.

Options: View larger image (or click on image) Download as PowerPoint
GATA2 Emberger mutants exhibit reduced DNA-binding affinity. (A) EMSA an...
(A) EMSA analyses using recombinant, purified GATA2 WT C-terminal zinc finger (CF) and mutants showing that Emberger mutants (red) exhibit negligible binding to the PROX1 –11 kb element. (B) Far-UV CD spectra and (C) 1-D H1 NMR spectra (amide region) of recombinant purified proteins at 25°C, pH 7.4 in 20 mM sodium phosphate, 50 mM NaCl, 1 mM DTT showing C373R is largely disordered and that T354M is partly disordered. (D) Structure of the C-terminal finger of GATA3 (cyan) bound to DNA (gray; Protein Data Bank accession code 4hc7 [http://www.rcsb.org/]) showing positions of mutated residues. Emberger mutations are shown as red sticks, residues that moderately affect DNA binding by EMSA are shown as magenta sticks, and those that show WT binding are shown as pink sticks. Other zinc-coordinating residues are shown as yellow sticks, and zinc as a gray sphere.