title: Prox1 physically and functionally interacts with COUP-TFII to specify lymphatic endothelial cell fate.
abstract: Specification of endothelial cell (EC) fate during vascular development is controlled by distinct key regulators. While Notch plays an essential role in induction of arterial phenotypes, COUP-TFII is required to maintain the venous EC identity. Homeodomain transcription factor Prox1 functions to reprogram venous ECs to lymphatic endothelial cells (LECs). Here, we report that the venous EC fate regulator COUP-TFII is expressed in LECs throughout development and physically interacts with Prox1 to form a stable complex in various cell types including LECs. We found that COUP-TFII functions as a coregulator of Prox1 to control several lineage-specific genes including VEGFR-3, FGFR-3, and neuropilin-1 and is required along with Prox1 to maintain LEC phenotype. Together, we propose that the physical and functional interactions of the 2 proteins constitute an essential part in the program specifying LEC fate and may provide the molecular basis for the hypothesis of venous EC identity being the prerequisite for LEC specification.
authors.affiliation: Department of Surgery, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, USA.
authors.forename: Sunju
authors.initials: S
authors.lastname: Lee
authors.forename: Jinjoo
authors.initials: J
authors.lastname: Kang
authors.forename: Jaehyuk
authors.initials: J
authors.lastname: Yoo
authors.forename: Sathish K
authors.initials: SK
authors.lastname: Ganesan
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Cook
authors.forename: Berenice
authors.initials: B
authors.lastname: Aguilar
authors.forename: Swapnika
authors.initials: S
authors.lastname: Ramu
authors.forename: Juneyong
authors.initials: J
authors.lastname: Lee
authors.forename: Young-Kwon
authors.initials: YK
authors.lastname: Hong
mesh_terms: D051837:COUP Transcription Factor II / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D019070:Cell Lineage / Q000502:physiology; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008208:Lymphatic System / Q000166:cytology / Q000196:embryology*; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*; D000098551:Prospero-Related Homeobox 1 Protein
chemical_list: D051837:COUP Transcription Factor II; D018398:Homeodomain Proteins; D025521:Tumor Suppressor Proteins; D000098551:Prospero-Related Homeobox 1 Protein; C095569:NR2F2 protein, human