Sequence Specific Targeting of poly-CUG Motifs

描述（由申请人提供）：强直性肌营养不良症是最常见的成人发病型肌营养不良症。强直性肌营养不良（DM）的病理学是由DMPK基因的3 '-非翻译区中的多聚CTG扩增驱动的。一旦翻译，DMPK转录物保留在核灶中，并且所得的RNA/蛋白质（RNP）复合物隔离肌盲蛋白以及一般转录因子。序列特异性靶向聚CUG基序并破坏蛋白质-RNA相互作用的小分子具有抑制所有上述RNA/蛋白质相互作用并治疗DM的根源的潜力，从而提供终身疾病缓解。因此，该项目的广泛，长期目标是开发序列特异性靶向poly-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）通过针对聚-CUG RNA靶标筛选半胱氨酸约束的噬菌体文库来鉴定序列特异性结合聚-CUG RNA寡核苷酸的环肽支架。2)为了合成半胱氨酸约束肽，我们确定和生物药理学表征其RNA结合特性。3)进行类似物合成，以鉴定保持RNA结合特性并增强稳定性的二硫键大环连接的模拟物。一旦环肽模拟物已被确定，未来的合作努力将针对评估在体内的潜力，每种化合物对破坏列入DMPK转录核灶，破坏肌盲蛋白与DMPK/RNP复合物的相互作用，并破坏RNP复合物和一般的转录因子之间的相互作用。公共卫生：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。本补助金中描述的治疗强直性肌营养不良的方法将是治疗DM根源的唯一方法，并将为独立于特定疾病症状的DM治疗提供途径，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.