CD151 is an abundantly expressed eukaryotic transmembrane protein on the cell surface. It is involved in cell adhesion, angiogenesis and signal transduction as well in disease conditions such as cancer and viral infections. However, the molecular mechanism of CD151 activation is poorly understood due to the lack of structural information. By considering the difficulties in expressing the membrane protein in E. coli, herein we introduce the strategic design for the effective expression of recombinant CD151 protein in E. coli with high yield, that would aid for the structural studies. CD151 having four transmembrane domain (TMD's) along with small and a large extracellular loop (LEL) is constructed in parts to enhance the soluble expression of the protein attached with fusion tag. This has led to the high yield of the recombinant CD151 protein in the designed constructs. The recombinant CD151 protein is characterized and confirmed by western blot, CD and Mass peptide fingerprint. The molecular dynamics simulations (MDS) for the full-length CD151 shows conformational changes in the LEL of the protein in the presence and absence of cholesterol and indicate the certainty of closed and open conformation of CD151 based on cholesterol binding. The MDS results have led to the understanding of the possible underlying mechanism for the activation of the CD151 protein.

中文翻译：

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重组CD151在大肠杆菌中的高产量表达以及对胆固醇结合结构域的结构分析。

CD151是在细胞表面上大量表达的真核跨膜蛋白。它参与细胞粘附，血管生成和信号转导以及疾病状况，例如癌症和病毒感染。但是，由于缺乏结构信息，人们对CD151活化的分子机制了解甚少。考虑到在大肠杆菌中表达膜蛋白的困难，本文介绍了在大肠杆菌中高效表达重组CD151蛋白的有效策略设计，这将有助于结构研究。具有四个跨膜结构域（TMD）以及大，小的细胞外环（LEL）的CD151被部分构建，以增强与融合标签连接的蛋白质的可溶性表达。这导致在设计的构建体中重组CD151蛋白的高产率。重组CD151蛋白的特征在于蛋白质印迹，CD和Mass肽指纹图谱，并得到了证实。全长CD151的分子动力学模拟（MDS）显示了在存在和不存在胆固醇的情况下蛋白质LEL的构象变化，并表明了基于胆固醇结合的CD151闭合和开放构象的确定性。MDS结果导致人们了解了CD151蛋白激活的潜在机制。全长CD151的分子动力学模拟（MDS）显示了在存在和不存在胆固醇的情况下蛋白质LEL的构象变化，并表明了基于胆固醇结合的CD151闭合和开放构象的确定性。MDS结果导致人们了解了CD151蛋白激活的潜在机制。全长CD151的分子动力学模拟（MDS）显示了在存在和不存在胆固醇的情况下蛋白质LEL的构象变化，并表明了基于胆固醇结合的CD151闭合和开放构象的确定性。MDS结果导致人们了解了CD151蛋白激活的潜在机制。