Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.48 (transcriptase)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiogenesis is fundamental to normal placental development. Aberrant angiogenesis within the placental terminal villi is a characteristic of significant placental pathologies and includes structural and vascular abnormalities as well as altered endothelial cell function, which substantially impacts on maternal-fetal exchange. Homeobox gene transcription factors regulate vascular development in embryonic and adult tissues, but their role in the placental microvasculature is not well known. In this study, we isolated and enriched human placental microvascular endothelial cells (PLEC) by a perfusion-based method and compared homeobox gene expression between PLEC and macrovascular human umbilical vein endothelial cells (HUVEC). Reverse transcriptase PCR detected mRNA expression of homeobox genes DLX3, DLX4, MSX2, GAX and HLX1 in both PLEC and HUVEC. DLX4 and HLX1 have not been previously detected in PLEC and with the exception of GAX, none of these homeobox genes have been previously identified in HUVEC. There was lower expression of HLX1 mRNA in HUVEC compared with PLEC. Using real-time PCR analysis PLEC HLX1 mRNA expression relative to housekeeping gene GAPDH was 0.9+/-0.06 fold of the calibrator (n=6) versus 0.2+/-0.06 (n=6) for HUVEC, p<0.001. These data provided evidence of heterogeneity in homeobox gene expression between microvascular PLEC and macrovascular HUVEC that most likely reflects significant differences in endothelial cell function in the two different cellular environments.
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PMID:Homeobox genes are differentially expressed in macrovascular human umbilical vein endothelial cells and microvascular placental endothelial cells. 1664 16

Angiogenesis is fundamental to normal placental development and aberrant angiogenesis contributes substantially to placental pathologies. The complex process of angiogenesis is regulated by transcription factors leading to the formation of endothelial cells that line the microvasculature. Homeobox genes are important transcription factors that regulate vascular development in embryonic and adult tissues. We have recently shown that placental homeobox genes HLX, DLX3, DLX4, MSX2 and GAX are expressed in placental endothelial cells. Hence, the novel homeobox genes TLX1, TLX2, TGIF, HEX, PHOX1, MEIS2, HOXB7, and LIM6 were detected that have not been reported in endothelial cells previously. Importantly, these homeobox genes have not been previously reported in placental endothelial cells and, with the exception of HEX, PHOX1 and HOXB7, have not been described in any other endothelial cell type. Reverse transcriptase PCR was performed on cDNA from freshly isolated placental microvascular endothelial cells (PLEC), and the human placental microvascular endothelial cell line HPEC. cDNAs prepared from control term placentae, human microvascular endothelial cells (HMVEC) and human umbilical vein macrovascular endothelial cells (HUVEC) were used as controls. PCR analyses showed that all novel homeobox genes tested were expressed by all endothelial cells types. Furthermore, real-time PCR analyses revealed that homeobox genes TLX1, TLX2 and PHOX1 relative mRNA expression levels were significantly decreased in HUVEC compared with microvascular endothelial cells, while the relative mRNA expression levels of MEIS2 and TGIF were significantly increased in macrovascular cells compared with microvascular endothelial cells. Thus we have identified novel homeobox genes in microvascular endothelial cells and have shown that homeobox genes are differentially expressed between micro- and macrovascular endothelial cells.
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PMID:Novel homeobox genes are differentially expressed in placental microvascular endothelial cells compared with macrovascular cells. 1851 8