Sequence Specific Targeting of poly-CUG Motifs

描述(申请人提供)：强直性肌营养不良症是最常见的成人起病肌营养不良症。强直性肌营养不良症(DM)的病理机制是由DMPK基因3‘非翻译区的多CTG扩增所致。一旦翻译，DMPK转录本保留在核内，所产生的RNA/蛋白质(RNP)复合体隔离肌肉蛋白以及一般转录因子。序列特异性靶向Poly-CUG基序并破坏蛋白质-RNA相互作用的小分子有可能抑制所有上述RNA/蛋白质相互作用，治疗糖尿病的根源，提供终身疾病缓解。因此，该项目的广泛、长期目标是开发序列特异性靶向多CUG基序并破坏蛋白质/RNA相互作用的环肽模拟物。为了实现这一目标，我们的具体目标是：1)通过筛选针对聚CUG RNA靶标的半胱氨酸受限噬菌体文库，鉴定与聚CUG RNA寡核苷酸序列特异性结合的环肽支架。2)合成我们鉴定的半胱氨酸限制性多肽，并对其与RNA的结合特性进行生物物理表征。3)进行模拟合成，以确定保持RNA结合特性和增强稳定性的二硫键大环键的模拟物。一旦确定了环肽模拟物，未来的合作努力将集中在评估每个化合物在体内的潜力，以破坏DMPK转录本在核焦点中的包含，破坏肌肉缺陷蛋白与DMPK/RNP复合体的相互作用，以及破坏RNP复合体与一般转录因子之间的相互作用。对公众健康：目前治疗强直性肌营养不良症的所有方法都依赖于症状管理。这笔赠款中描述的治疗强直性肌营养不良症的方法将是治疗糖尿病根源的唯一方法，并将为糖尿病治疗提供一种独立于特定疾病症状的途径，并有可能提供终身疾病缓解。

DESCRIPTION (provided by applicant): Myotonic Dystrophy is the most prevalent adult onset muscular dystrophy. The pathology of Myotonic Dystrophy (DM) is driven by a poly-CTG expansion in the 3'- untranslatated region of the DMPK gene. Once translated, the DMPK transcript retained in nuclear foci, and the resulting RNA/protein (RNP) complex sequesters muscleblind proteins as well as general transcription factors. Small molecules that sequence- specifically target poly-CUG motifs and disrupt protein-RNA interactions have the potential to inhibit all the aforementioned RNA/protein interactions and treat the root of DM, providing lifelong disease remission. Therefore, the broad, long-term objective of this project is the development of cyclic peptide mimics that sequence-specifically target poly-CUG motifs and disrupt protein/RNA interactions. To achieve this objective, our Specific Aims are: 1) to identify cyclic peptide scaffolds that sequence-specifically bind poly-CUG RNA oligonucleotides by screening cysteine-constrained phage libraries against a poly-CUG RNA target. 2) To synthesize the cysteine-constrained peptides that we identify and biophysically characterize their RNA binding properties. 3) To conduct analog synthesis to identify mimics for the disulfide macrocyclic linkage that maintain RNA-binding properties and enhance stability. Once cyclic peptide mimics have been identified, future collaborative efforts will be directed toward assessing the in vivo potential of each compound toward disrupting the inclusion of the DMPK transcript in nuclear foci, disrupting the interaction of muscleblind proteins with the DMPK/RNP complex, and disrupting the interaction between the RNP complex and general transcription factors. to public health: All current approaches to treating Myotonic Dystrophy rely upon symptom management. The approach to treating Myotonic Dystrophy that is delineated in this grant will be the only approach that treats the root of DM and will provide an avenue for DM therapy that is independent of the specific disease symptoms and has the potential to provide lifelong disease remission.