As described in the goals and objectives section of this report, this project consists of two specific aims: Studying genes regulating vascular integrity We have used forward-genetic screens to identify new zebrafish mutants that disrupt cranial vascular integrity in the zebrafish, using exome sequencing and SNP analysis with a newly developed SNP database to perform higher-throughput cloning of mutants. We have already characterized the role of GDF6 (BMP13) in vascular integrity, demonstrating that this gene promotes maintenance of vascular integrity by suppressing excess VEGF signaling. We are currently characterizing the molecular nature of the defects in these mutants, and continuing to identify the causative genetic defects in the other mutants. These new vascular integrity mutants promise to bring to light new pathways important in the maintenance of vascular barrier function. Studying the acquisition and function of supporting vascular smooth muscle cells The vascular smooth cells (VSMC) that surround the endothelial tube play a critical role in regulating vascular tone and vascular integrity. We have recently begun examining the acquisition and function of these cells using the zebrafish. We have developed a number of useful transgenic tools to visualize and experimentally manipulate this cell population in the zebrafish, and are using these and other tools to, among other things, (i) examine the origins of these cells from early sclerotome, (ii) demonstrate that VSMC interaction with the endothelium us required to maintain the vascular basement membrane and restrict vessel diameter, (iii) elucidate the molecular pathways responsible for the selective acquisition of VSMC by arteries (as opposed to veins). Studying the vasculature and vascular-associated cells in the meninges The meninges are an external enveloping connective tissue that encases the brain, producing cerebrospinal fluid, acting as a cushion against trauma, nourishing the brain via nutrient circulation, and removing waste. Despite its importance, the cell types present in the meninges and the function and embryonic origins of this tissue are still not well understood. We recently discovered a novel perivascular cell population closely associated with blood vessels on the zebrafish brain. Based on similarities in their morphology, location, and highly unusual scavenger behavior, these cells appear to be the zebrafish equivalent of mammalian Fluorescent Granular Perithelial cells (FGPs), macrophage-like cells about which very little is known that likely play important roles in brain function and in a variety of CNS pathologies. Despite their macrophage-like morphology and their perivascular location these cells are molecularly most similar to lymphatic endothelial cells and they transdifferentiate from primitive endothelium deep inside the brain before migrating to the brain surface. Using forward-genetic screening of transgenic zebrafish for ENU-induced recessive mutations, we recently identified a mutant that appears to be specifically deficient in FGPs, providing a genetic model that we are using to further explore the important functional role of these cells. Our findings thus far provide the first report of a non-vessel forming, perivascular cell population in the brain that emerges by transdifferentiation from vascular endothelium. We are further exploring the structure, cellular composition, and functional roles of meningeal vascular-associated cell populations using the zebrafish model.
| Nowak-Sliwinska, Patrycja; Alitalo, Kari; Allen, Elizabeth et al. (2018) Consensus guidelines for the use and interpretation of angiogenesis assays. Angiogenesis 21:425-532 |
| Krispin, Shlomo; Stratman, Amber N; Melick, Chase H et al. (2018) Growth Differentiation Factor 6 Promotes Vascular Stability by Restraining Vascular Endothelial Growth Factor Signaling. Arterioscler Thromb Vasc Biol 38:353-362 |
| Stratman, Amber N; Pezoa, Sofia A; Farrelly, Olivia M et al. (2017) Interactions between mural cells and endothelial cells stabilize the developing zebrafish dorsal aorta. Development 144:115-127 |
| Stainier, Didier Y R; Raz, Erez; Lawson, Nathan D et al. (2017) Guidelines for morpholino use in zebrafish. PLoS Genet 13:e1007000 |
| Venero Galanternik, Marina; Castranova, Daniel; Gore, Aniket V et al. (2017) A novel perivascular cell population in the zebrafish brain. Elife 6: |
| Ulrich, Florian; Carretero-Ortega, Jorge; Menéndez, Javier et al. (2016) Reck enables cerebrovascular development by promoting canonical Wnt signaling. Development 143:1055 |
| Kallakuri, Sowjanya; Yu, Jianxin A; Li, Jade et al. (2015) Endothelial cilia are essential for developmental vascular integrity in zebrafish. J Am Soc Nephrol 26:864-75 |
| Miskinyte, Snaigune; Butler, Matthew G; Herve, Dominique et al. (2011) Loss of BRCC3 deubiquitinating enzyme leads to abnormal angiogenesis and is associated with syndromic moyamoya. Am J Hum Genet 88:718-28 |
| Butler, Matthew G; Gore, Aniket V; Weinstein, Brant M (2011) Zebrafish as a model for hemorrhagic stroke. Methods Cell Biol 105:137-61 |
| Fujita, Misato; Cha, Young R; Pham, Van N et al. (2011) Assembly and patterning of the vascular network of the vertebrate hindbrain. Development 138:1705-15 |
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