Alluri Prasanna, Liu Bo, Yu Peng, Xiao Xiangshu, Kodadek Thomas
Division of Translational Research, Department of Internal Medicine and Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9185, USA.
Mol Biosyst. 2006 Nov;2(11):568-79. doi: 10.1039/b608924k. Epub 2006 Sep 26.
Pharmacologic agents capable of activating the expression of specific genes would be valuable tools in biological research and could potentially be useful therapeutically. Efforts to develop a general solution to this problem have focused on the discovery of cell permeable mimics of native transcription factors comprised of linked DNA-binding and activation domain surrogates. Recently, we reported the isolation of a peptoid, called KBPo2, that binds a fragment of the mammalian coactivator CREB-binding protein (CBP). When delivered to a promoter-bound DNA-binding domain, this peptoid acted as a potent activation domain mimic in human cells. In this paper, we provide full details of the screening experiments and also report further characterization of this molecule as well as the other peptoids that came out of the screen. Of the three peptoids identified as putative CBP ligands, only KBPo2 demonstrated the necessary combination of binding affinity, specificity and cell permeability necessary to function as a potent activation domain mimic in cells. KBPo2 binds to CBP in a region different than that recognized by the native activation peptide from the transcription factor CREB.
能够激活特定基因表达的药物制剂在生物学研究中是很有价值的工具，并且在治疗方面可能具有潜在用途。为开发解决这一问题的通用方法所做的努力主要集中在发现由连接的DNA结合和激活结构域替代物组成的天然转录因子的细胞可渗透模拟物。最近，我们报道了一种名为KBPo2的类肽的分离，它能结合哺乳动物共激活因子CREB结合蛋白（CBP）的一个片段。当将这种类肽递送至与启动子结合的DNA结合结构域时，它在人类细胞中充当一种有效的激活结构域模拟物。在本文中，我们提供了筛选实验的完整细节，并且还报告了对该分子以及筛选出的其他类肽的进一步表征。在被鉴定为假定CBP配体的三种类肽中，只有KBPo2表现出在细胞中充当有效激活结构域模拟物所需的结合亲和力、特异性和细胞渗透性的必要组合。KBPo2与CBP结合的区域不同于转录因子CREB的天然激活肽所识别的区域。
