Regulation of transcriptional activation by protein disorder

蛋白质紊乱对转录激活的调控 PIS：Daughdrill/Chen 摘要 P53肿瘤抑制因子是一种序列特异性DNA结合蛋白，可激活基因转录 来调节细胞的存活和增殖。它在至少50%的实体肿瘤中发生突变，其中一些 突变体是致癌的，并激活促进细胞存活和转移的基因的转录。 尽管对p53的研究已经有几十年了，但目前还没有FDA批准的临床药物直接 靶向wt或突变型p53。这在一定程度上是因为50%的P53是无序的，我们有一个不完整的 了解这些区域的外观和功能。我们最近已经表明， 无序的p53 N末端酸性反式激活结构域(NT)与DNA动态相互作用 与DNA接触的残基的结合域(DBD)。这种相互作用会抑制DNA结合，但 使用核酸模拟和静电屏蔽的组合来提高结合特异性 增强体内启动子结合位点的识别。我们建议：(1)确定具体效果 核酸模拟和静电屏蔽对DNA结合特异性的影响，以及拴系是如何控制的 NT与DBD之间的分子内相互作用。(2)研究P53-NT如何磷酸化 调节DNA结合亲和力和特异性，以创造转录激活的适应性切换。 (3)确定MDMX与P53形成异源二聚体时如何干扰P53 DNA结合。 这些实验的成功完成将有助于更好地理解P53是如何调控细胞的 通过调节促生存和促凋亡靶标的结合特异性来调节DNA损伤后的命运 基因。对弱动力学的结构和功能性质有了更深的理解 P53内部以及P53和MDMX之间的相互作用是成功发展肿瘤所必需的 小分子将这些相互作用作为癌症治疗的靶点。

Regulation of transcriptional activation by protein disorder PIs: Daughdrill/Chen Abstract The p53 tumor suppressor is a sequence-specific DNA binding protein that activates gene transcription to regulate cell survival and proliferation. It is mutated in at least 50% of solid tumors and some of these mutants are oncogenic and activate the transcription of genes that promote cell survival and metastasis. Despite decades of research on p53, there are currently no FDA approved drugs in the clinic that directly target wt or mutant p53. This is, in part, because 50% of p53 is disordered and we have an incomplete understanding of what these regions look like and how they function. We have recently shown that the disordered N-terminal acidic transactivation domain of p53 (NT) dynamically interacts with the DNA binding domain (DBD) with residues that contact DNA. This interaction inhibits DNA binding but increases binding specificity using a combination of nucleic acid mimicry and electrostatic shielding that enhances recognition of promoter binding sites in vivo. We propose to: (1) Determine the specific effects of nucleic acid mimicry and electrostatic shielding on DNA binding specificity, and how tethering controls the intramolecular interaction between NT and DBD. (2) Investigate how p53 NT phosphorylation regulates DNA binding affinity and specificity to create adaptable switching of transcriptional activation. (3) Determine how MdmX interferes with p53 DNA binding when it forms a heterodimer with p53. Successful completion of these experiments will lead to a better understanding of how p53 governs cell fate after DNA damage by regulating the binding specificity to pro-survival versus pro-apoptotic target genes. A deeper understanding of the structural and functional properties of the weak dynamic interactions within p53 and between p53 and MdmX is necessary for the successful development of small molecules to target these interactions for cancer therapy.