Department of Pharmacology, College of Medicine, Institute of Natural Medicine, Hallym University, Chuncheon 24252, Korea.
Sanford Burnham Prebys Medical Discovery Institute, CA 92037, USA.
Mol Cells. 2019 Feb 28;42(2):123-134. doi: 10.14348/molcells.2018.0399. Epub 2019 Jan 2.
Lysophosphatidic acid (LPA) is an endogenous lysophospholipid with signaling properties outside of the cell and it signals through specific G protein-coupled receptors, known as LPA. For one of its receptors, LPA (gene name , details on the cis-acting elements for transcriptional control have not been defined. Using 5'RACE analysis, we report the identification of an alternative transcription start site of mouse and characterize approximately 3,500 bp of non-coding flanking sequence 5' of mouse gene for promoter activity. Transient transfection of cells derived from mouse neocortical neuroblasts with constructs from the 5' regions of mouse gene revealed the region between -248 to +225 serving as the basal promoter for . This region also lacks a TATA box. For the region between -761 to -248, a negative regulatory element affected the basal expression of . This region has three E-box sequences and mutagenesis of these E-boxes, followed by transient expression, demonstrated that two of the E-boxes act as negative modulators of . One of these E-box sequences bound the HeLa E-box binding protein (HEB), and modulation of HEB levels in the transfected cells regulated the transcription of the reporter gene. Based on our data, we propose that HEB may be required for a proper regulation of expression in the embryonic neocortical neuroblast cells and to affect its function in both normal brain development and disease settings.
溶血磷脂酸（LPA）是一种内源性溶血磷脂，具有细胞外的信号转导特性，通过特定的 G 蛋白偶联受体（LPA）进行信号转导。对于其受体之一，LPA（基因名称），转录控制的顺式作用元件的细节尚未定义。通过 5'RACE 分析，我们报告了鉴定出的小鼠的替代转录起始位点，并对小鼠基因的非编码侧翼序列的大约 3500 bp 进行了特征分析5'对于启动子活性。用来自小鼠新皮质神经母细胞瘤的细胞的构建体瞬时转染，揭示了 -248 到 +225 之间的区域作为小鼠的基础启动子。该区域也缺乏 TATA 盒。对于 -761 到 -248 之间的区域，负调控元件影响了的基础表达。该区域有三个 E-box 序列，这些 E-box 的突变，随后进行瞬时表达，表明其中两个 E-box 作为的负调节剂。这些 E-box 序列之一结合了 HeLa E-box 结合蛋白（HEB），并且转染细胞中 HEB 水平的调节调节了报告基因的转录。根据我们的数据，我们提出 HEB 可能是胚胎新皮质神经母细胞中正确调节表达所必需的，并且可以影响其在正常大脑发育和疾病环境中的功能。
