A photo of Saulius Sumanas.

Associate Professor, UC Department of Pediatrics



Biography & Affiliation


I’m a vascular researcher who studies the molecular mechanisms of vascular formation. I aim to apply my scientific findings to the development of new treatment strategies for human vascular disorders.

The mechanisms that control vasculogenesis (blood vessel formation de novo) and angiogenesis (blood vessels that sprout from existing vessels) are still poorly understood. Fortunately, the zebrafish has emerged as an advantageous model organism to study how the evolutionarily conserved network of vertebrate blood vessels form during development — and to discover mechanisms that regulate this development.

Because transparent zebrafish embryos develop externally, we can easily observe the finest details of blood vessel development in live embryos using light microscopy. Also, zebrafish embryos often develop for several days in the complete absence of blood circulation, which allows for an accurate analysis of defects in vascular mutants.

Because of these advantages, our lab utilizes zebrafish as a model to study the molecular mechanisms of vasculature development. We are examining transcriptional regulation during embryonic vasculogenesis and angiogenesis, as well as pathological vascular development, such as tumor angiogenesis. We are also performing screens for novel potential regulators of vasculature formation, followed by characterization and functional studies. Finally, we’re using zebrafish as a model system to identify genetic causes of different human vascular diseases, including intracranial aneurysms.

Among our major findings to date, we’ve used zebrafish embryos to demonstrate the distinct origin of arterial and venous progenitors, which led to a new model of arterial-venous specification. In another notable discovery, we identified developmental signals that regulate specification and differentiation of the heart endocardial layer. We’ve also identified collagen COL22A1 as a candidate gene affected in intracranial aneurysms and analyzed the ways transcription factor Etv2 regulates the choice between vascular endothelial, cardiomyocyte and skeletal muscle lineages.

My research is supported by a variety of internal and external funding. In 2017, I received an NIH R01 award for my study, "The role of Collagen COL22A1 in intracranial aneurysms and vascular stability."

Research Interests

Vascular development, angiogenesis, zebrafish models of human diseases

Academic Affiliation

Associate Professor, UC Department of Pediatrics

Research Divisions

Developmental Biology


BS: Vilnius University, Biochemistry, Vilnius, Lithuania, 1995.

PhD: University of Minnesota, Department of Biochemistry, Minneapolis / St. Paul, MN, 2000.

Postdoctoral Fellow: University of California, Los Angeles, CA, 2002-2007.


Single-cell transcriptomic analysis identifies the conversion of zebrafish Etv2-deficient vascular progenitors into skeletal muscle. Chestnut, B; Casie Chetty, S; Koenig, AL; Sumanas, S. Nature Communications. 2020; 11.

Ets1 functions partially redundantly with Etv2 to promote embryonic vasculogenesis and angiogenesis in zebrafish. Casie Chetty, S; Sumanas, S. Developmental Biology. 2020; 465:11-22.

Integrin α5 and Integrin α4 cooperate to promote endocardial differentiation and heart morphogenesis. Schumacher, JA; Wright, ZA; Owen, ML; Bredemeier, NO; Sumanas, S. Developmental Biology. 2020; 465:46-57.

Zebrafish etv2 knock-in line labels vascular endothelial and blood progenitor cells. Chestnut, B; Sumanas, S. Developmental Dynamics. 2020; 249:245-261.

Clec14a genetically interacts with Etv2 and Vegf signaling during vasculogenesis and angiogenesis in zebrafish. Pociute, K; Schumacher, JA; Sumanas, S. BMC Developmental Biology. 2019; 19.

Collagen COL22A1 maintains vascular stability and mutations in COL22A1 are potentially associated with intracranial aneurysms. Ton, QV; Leino, D; Mowery, SA; Bredemeier, NO; Lafontant, PJ; Lubert, A; Gurung, S; Farlow, JL; Foroud, TM; Broderick, J; et al. DMM Disease Models and Mechanisms. 2018; 11.

ETS transcription factor Etsrp / Etv2 is required for lymphangiogenesis and directly regulates vegfr3 / flt4 expression. Davis, JA; Koenig, AL; Lubert, A; Chestnut, B; Liu, F; Desai, SP; Winkler, T; Pociute, K; Choi, K; Sumanas, S. Developmental Biology. 2018; 440:40-52.

Wnt signaling positively regulates endothelial cell fate specification in the Fli1a-positive progenitor population via Lef1. Hubner, K; Grassme, KS; Rao, J; Wenke, NK; Zimmer, CL; Korte, L; Mueller, K; Sumanas, S; Greber, B; Herzog, W. Developmental Biology. 2017; 430:142-155.

ETS transcription factors Etv2 and Fli1b are required for tumor angiogenesis. Baltrunaite, K; Craig, MP; Desai, SP; Chaturvedi, P; Pandey, RN; Hegde, RS; Sumanas, S. Angiogenesis. 2017; 20:307-323.

Vegf signaling promotes vascular endothelial differentiation by modulating etv2 expression. Chetty, SC; Rost, MS; Enriquez, JR; Schumacher, JA; Baltrunaite, K; Rossi, A; Stainier, DY R; Sumanas, S. Developmental Biology. 2017; 424:147-161.