Tsao Ku-Chi, Lin Yuh-Charn, Chen Yi-Ting, Lai Shih-Lei, Yang Ruey-Bing
Program in Molecular Medicine, National Yang Ming Chiao Tung University and Academia Sinica, 155, Sec. 2, Linong Street, Taipei 112304, Taiwan.
Institute of Biomedical Sciences, Academia Sinica, 128, Sec. 2, Academia Road, Taipei 115201, Taiwan.
Cardiovasc Res. 2022 Mar 16;118(4):1074-1087. doi: 10.1093/cvr/cvab125.
The secreted and membrane-anchored signal peptide-CUB-EGF domain-containing proteins (SCUBE) gene family composed of three members was originally identified from endothelial cells (ECs). We recently showed that membrane SCUBE2 binds vascular endothelial growth factor (VEGF) and acts as a co-receptor for VEGF receptor 2 to modulate EC migration, proliferation, and tube formation during postnatal and tumour angiogenesis. However, whether these SCUBE genes cooperate in modulating VEGF signalling during embryonic vascular development remains unknown.
To further dissect the genetic interactions of these scube genes, transcription activator-like effector nuclease-mediated genome editing was used to generate knockout (KO) alleles of each scube gene. No overt vascular phenotypes were seen in any single scube KO mutants because of compensation by other scube genes during zebrafish development. However, scube1 and scube2 double KO (DKO) severely impaired EC filopodia extensions, migration, and proliferation, thus disrupting proper vascular lumen formation during vasculogenesis and angiogenesis as well as development of the organ-specific intestinal vasculature. Further genetic, biochemical, and molecular analyses revealed that Scube1 and Scube2 might act cooperatively at the cell-surface receptor level to facilitate Vegfa signalling during zebrafish embryonic vascularization.
We showed for the first time that cooperation between scube1 and scube2 is critical for proper regulation of angiogenic cell behaviours and formation of functional vessels during zebrafish embryonic development.
分泌型和膜锚定的含信号肽-CUB-EGF结构域蛋白（SCUBE）基因家族由三个成员组成，最初是在内皮细胞中鉴定出来的。我们最近发现膜结合型SCUBE2可结合血管内皮生长因子（VEGF），并作为VEGF受体2的共受体，在出生后和肿瘤血管生成过程中调节内皮细胞迁移、增殖和管腔形成。然而，在胚胎血管发育过程中，这些SCUBE基因是否协同调节VEGF信号通路仍不清楚。
为了进一步剖析这些scube基因的遗传相互作用，利用转录激活样效应核酸酶介导的基因组编辑技术产生每个scube基因的敲除（KO）等位基因。由于斑马鱼发育过程中其他scube基因的补偿作用，在任何单个scube基因敲除突变体中均未观察到明显的血管表型。然而，scube1和scube2双敲除（DKO）严重损害了内皮细胞丝状伪足的延伸、迁移和增殖，从而破坏了血管生成和血管新生过程中正常的血管腔形成以及器官特异性肠道血管系统的发育。进一步的遗传学、生物化学和分子分析表明，在斑马鱼胚胎血管形成过程中，Scube1和Scube2可能在细胞表面受体水平协同作用，促进Vegfa信号传导。
我们首次表明，scube1和scube2之间的协同作用对于斑马鱼胚胎发育过程中血管生成细胞行为的正常调节和功能性血管的形成至关重要。
