PDF(Pubmed)
Abstract：
OBJECTIVE: Disruptor of telomeric silencing 1-like (DOT1L) is the only known histone H3K79 methyltransferase essential for the development of the embryonic cardiovascular system, including the heart, blood vessels, and lymphatic vessels, through transcriptional regulation. Our previous study demonstrated that Dot1l deletion results in aberrant lymphatic development and function. However, its precise function in the postnatal cardiovascular system remains unknown.
METHODS: Using conditional and inducible Dot1l knockout (KO) mice, along with a reporter strain carrying the Geo gene at the Dot1l locus, DOT1L expression and its function in the vascular system during postnatal life were investigated. To assess vessel morphology and vascular permeability, we administered Latex or Evans blue dye to KO mice. In addition, in vitro tube formation and cell migration assays were performed using DOT1L-depleted human umbilical vein endothelial cells (HUVECs). Changes in the expression of vascular genes in HUVECs were measured by quantitative polymerase chain reaction.
RESULTS: Our findings demonstrate that conditional Dot1l knockout in the Tg (Tie2-cre) strain results in abnormal blood vessel formation and lymphatic anomalies in the intestine. In a mouse model of Rosa26-creER-mediated inducible Dot1l knockout, we observed vascular phenotypes, including increased vascular permeability and brain hemorrhage, when DOT1L was deleted in adulthood. Additionally, DOT1L depletion in cultured HUVECs led to impaired cell migration and tube formation, likely due to altered gene transcription. These findings highlight the essential role of DOT1L in maintaining vascular integrity and function during embryonic development and postnatal life.
CONCLUSIONS: Our study revealed that DOT1L is required for the maintenance of adult vascular function through the regulation of gene expression.
METHODS: Using conditional and inducible Dot1l knockout (KO) mice, along with a reporter strain carrying the Geo gene at the Dot1l locus, DOT1L expression and its function in the vascular system during postnatal life were investigated. To assess vessel morphology and vascular permeability, we administered Latex or Evans blue dye to KO mice. In addition, in vitro tube formation and cell migration assays were performed using DOT1L-depleted human umbilical vein endothelial cells (HUVECs). Changes in the expression of vascular genes in HUVECs were measured by quantitative polymerase chain reaction.
RESULTS: Our findings demonstrate that conditional Dot1l knockout in the Tg (Tie2-cre) strain results in abnormal blood vessel formation and lymphatic anomalies in the intestine. In a mouse model of Rosa26-creER-mediated inducible Dot1l knockout, we observed vascular phenotypes, including increased vascular permeability and brain hemorrhage, when DOT1L was deleted in adulthood. Additionally, DOT1L depletion in cultured HUVECs led to impaired cell migration and tube formation, likely due to altered gene transcription. These findings highlight the essential role of DOT1L in maintaining vascular integrity and function during embryonic development and postnatal life.
CONCLUSIONS: Our study revealed that DOT1L is required for the maintenance of adult vascular function through the regulation of gene expression.
摘要：
■DOT1L是唯一已知的对胚胎心血管系统发育至关重要的组蛋白H3K79甲基转移酶，包括心脏,血管,和淋巴管，通过转录调控。我们先前的研究证明Dotll缺失导致异常的淋巴发育和功能。然而,其在产后心血管系统中的确切功能仍然未知。
■使用条件和诱导型Dot1l敲除（KO）小鼠，以及在Dot1l基因座携带Geo基因的报告菌株，研究了出生后生活中DOT1L的表达及其在血管系统中的功能。为了评估血管形态和血管通透性，我们给KO小鼠施用乳胶或伊文思蓝染料。此外,使用DOT1L耗尽的人脐静脉内皮细胞(HUVECs)进行体外试管形成和细胞迁移试验.通过定量聚合酶链反应测量HUVECs中血管基因表达的变化。
■我们的发现表明，Tg（Tie2-cre）菌株中的条件性Dot1l敲除会导致肠道中异常的血管形成和淋巴异常。在Rosa26-creER介导的诱导型Dot1l敲除的小鼠模型中，我们观察到血管表型,包括血管通透性增加和脑出血,当DOT1L在成年期被删除时。此外,培养的HUVEC中DOT1L耗竭导致细胞迁移和试管形成受损，可能是由于基因转录改变。这些发现强调了DOT1L在维持胚胎发育和出生后生活期间血管完整性和功能方面的重要作用。
■我们的研究表明，DOT1L是通过调节基因表达来维持成人血管功能所必需的。
■使用条件和诱导型Dot1l敲除（KO）小鼠，以及在Dot1l基因座携带Geo基因的报告菌株，研究了出生后生活中DOT1L的表达及其在血管系统中的功能。为了评估血管形态和血管通透性，我们给KO小鼠施用乳胶或伊文思蓝染料。此外,使用DOT1L耗尽的人脐静脉内皮细胞(HUVECs)进行体外试管形成和细胞迁移试验.通过定量聚合酶链反应测量HUVECs中血管基因表达的变化。
■我们的发现表明，Tg（Tie2-cre）菌株中的条件性Dot1l敲除会导致肠道中异常的血管形成和淋巴异常。在Rosa26-creER介导的诱导型Dot1l敲除的小鼠模型中，我们观察到血管表型,包括血管通透性增加和脑出血,当DOT1L在成年期被删除时。此外,培养的HUVEC中DOT1L耗竭导致细胞迁移和试管形成受损，可能是由于基因转录改变。这些发现强调了DOT1L在维持胚胎发育和出生后生活期间血管完整性和功能方面的重要作用。
■我们的研究表明，DOT1L是通过调节基因表达来维持成人血管功能所必需的。
