Dataset Information

The histone acetyltransferase HBO1 (KAT7) promotes efficient tip cell sprouting during angiogenesis

ABSTRACT: Blood vessel growth and remodelling are essential during embryonic development and disease pathogenesis. The diversity of endothelial cells (ECs) is transcriptionally evident and ECs undergo dynamic changes in gene expression during vessel growth and remodelling.Here, we investigated the role of the histone acetyltransferase HBO1 (KAT7), which is important for activating genes during development and histone H3 lysine 14 acetylation (H3K14ac). Loss of HBO1 and H3K14ac impaired developmental sprouting angiogenesis and reduced pathological EC overgrowth in the retinal endothelium. Single-cell RNA-sequencing of retinal ECs revealed an increased abundance of tip cells in Hbo1 deleted retinas, which lead to EC overcrowding in the retinal sprouting front and prevented efficient tip cell migration. We found that H3K14ac was highly abundant in the endothelial genome in both intra- and intergenic regions suggesting that the role of HBO1 is as a genome organiser that promotes efficient tip cell behaviour necessary for sprouting angiogenesis.

ORGANISM(S): Homo sapiens

PROVIDER: GSE161236 | GEO | 2021/09/30

REPOSITORIES: GEO

ACCESS DATA

Shared Molecules

Only show the datasets with similarity scores above: 0.5

Threshold

0.5

Similar Datasets

Project description:Although mitochondrial activity is critical for angiogenesis, its mechanism is not entirely clear. Here, we investigate the angiogenic functions of three separate nuclear genes that encode for mitochondrial proteins, including mitochondrial transcriptional factor (TFAM), respiratory complex IV component (COX10), and a mitochondrial redox protein thioredoxin 2 (TRX2), which are responsible for distinct mitochondrial functions. We aim to investigate if mitochondrial activities regulate common endothelial cell (EC) signaling pathways during angiogenesis. The silencing of Tfam, Cox10, or Trx2 in an in vitro 3D sprouting assay attenuates EC sprouting, which correlated with reduced EC proliferation but not with ROS generation or EC apoptosis. Mice with an inducible deletion of Tfam, Cox10, or Trx2 exhibit retarded retinal vessel growth without penetration into the deep plexi at early ages (P5-P12). The three mutant mice develop arteriovenous malformations (AVM) with microaneurysm formation in the microvessels at advanced ages (P12-P30); the hypovasculature and microaneurysm phenotypes resemble that of aged human retinas and human primitive retinal vascular abnormalities such as Coats’ disease, Leber’s military aneurysms and familial exudative vitreoretinopathy. Single-cell RNA-seq analyses of retinal ECs suggest that the three mutant mice have common EC clusters with reduced gene expressions in anion transporters, actin organization, extracellular matrix, and angiogenesis. These EC clusters also have increased gene expressions in endothelial-mesenchymal transition and arterial markers, correlating with enhanced TGFbR signaling in Tfam, Cox10, or Trx2-deficient mice. Importantly, pharmacological blockade by TGFbR inhibitors attenuated retinal vessel growth retardation and AVM formation in all three mutant mice. Our study demonstrates that mitochondrial dysfunction induces TGF-b receptor-mediated arteriovenous malformations and microaneurysm formation in mouse retinas, and provide a novel model and therapeutic intervention for human primitive retinal vascular abnormalities, which are characterized by retinal vascular malformations and are associated with many pathological complications such as diabetes and hypertension that can result in vision loss.