HUMAN PYRUVATE KINASE ISOFORM 2 BINDING

人丙酮酸激酶异构体 2 结合

• 批准号: 7955215
• 负责人: LEWIS C. CANTLEY
• 金额: $ 1.72万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7955215
• 关键词: Adult; Back; Binding; Computer Retrieval of Information on Scientific Projects Database; Drug Delivery Systems; Enzymes; Erythrocytes; Exons; Funding; Genes; Grant; Human; Inhibitory Concentration 50; Institution; Lead; Liver; Modification; Mutagenesis; Normal tissue morphology; Nutrient; Peptide Library; Phosphopeptides; Phosphotyrosine; Protein Isoforms; Pyruvate Kinase; RNA Splicing; Regulation; Research; Research Personnel; Resources; Source; Structure; Tissues; United States National Institutes of Health; Variant; adult stem cell; blastomere structure; cancer cell; cancer therapy; deprivation; enzyme activity; inhibitor/antagonist; structural biology; tumor

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Pyruvate kinase is an essential glycolytic enzyme whose activity is highly regulated. There are 4 isoforms of the enzyme. The R and L isoforms are specific for red blood cells and liver respectively. The other two isoforms, M1 and M2, are splice variant of the same gene with only one exon difference. While the M2 isoform is highly expressed in embryonic cells and adult stem cells, most adult tissues express the M1 isoform. However, all cancer cells are found to switch back completely M2 expression. Although the cause of this switch is currently unknown, this differential expression between normal tissues and tumor makes the M2 isoform a drug target for cancer treatment. We have found several compounds that specifically inhibit the M2 isoform and not the M1 isoform. Since the lead compounds still have fairly high IC50, we would like to determine the structure of M2 bound to the inhibitors so rational modification can be made to generate better compounds. In addition, in contrast to PKM1 or the L isoforms, PKM2 preferentially interacts with phosphotyrosine peptide libraries. From mutagenesis studies, we also found that this interaction reduces its enzyme activity, presumably by displacing the allosteric activator FBP. This may explain why cancer cells have PKM2 isoform, since the extra level of control is advantageous for cancer cells to respond to deprivation of nutrients. In order to understand the regulation of PKM2 activity better, we would like to see at the atomic level, how the phosphopeptide competes with FBP.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 丙酮酸激酶是一种重要的糖酵解酶，其活性受到高度调节。该酶有4种同工型。R和L同种型分别对红细胞和肝脏具有特异性。另外两种亚型M1和M2是同一基因的剪接变体，只有一个外显子不同。虽然M2亚型在胚胎细胞和成体干细胞中高度表达，但大多数成体组织表达M1亚型。然而，发现所有癌细胞完全转回M2表达。虽然这种转换的原因目前尚不清楚，但正常组织和肿瘤之间的这种差异表达使M2亚型成为癌症治疗的药物靶标。我们已经发现了几种化合物，特异性抑制M2亚型，而不是M1亚型。由于先导化合物仍然具有相当高的IC50，我们希望确定与抑制剂结合的M2的结构，以便进行合理的修饰以产生更好的化合物。此外，与PKM1或L亚型相反，PKM2优先与磷酸酪氨酸肽库相互作用。从诱变研究中，我们还发现，这种相互作用降低了其酶活性，可能是通过取代变构激活剂FBP。这可以解释为什么癌细胞具有PKM2亚型，因为额外的控制水平有利于癌细胞对营养素缺乏做出反应。为了更好地理解PKM2活性的调节，我们希望在原子水平上看到磷酸肽如何与FBP竞争。