Sequence Specific Targeting of poly-CUG Motifs

描述（申请人提供）：肌强直性营养不良症是最常见的成人发病肌肉营养不良症。肌强直性营养不良（DM）的病理是由DMPK基因3'-非翻译区域的多ctg扩增驱动的。一旦翻译，DMPK转录物保留在核病灶中，由此产生的RNA/蛋白（RNP）复合物将肌盲蛋白以及一般转录因子隔离。序列特异性靶向多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/蛋白质相互作用并治疗DM的根源，提供终身疾病缓解。因此，该项目的长期目标是开发环肽模拟物，该模拟物序列特异性靶向多cug基序并破坏蛋白质/RNA相互作用。为了实现这一目标，我们的具体目标是：1)通过筛选针对多cug RNA靶点的半胱氨酸约束噬菌体文库，鉴定序列特异性结合多cug RNA寡核苷酸的环肽支架。2)合成经鉴定的半胱氨酸约束肽，并对其RNA结合特性进行生物物理表征。3)通过模拟物合成，鉴定二硫大环键的模拟物，维持rna结合特性，增强稳定性。一旦环状肽模拟物被确定，未来的合作努力将指向评估每种化合物在体内的潜力，以破坏DMPK转录物在核中心的包涵，破坏肌肉盲蛋白与DMPK/RNP复合物的相互作用，以及破坏RNP复合物与一般转录因子之间的相互作用。对公众健康：目前所有治疗强直性肌营养不良的方法都依赖于症状管理。本研究中描述的肌强直性营养不良的治疗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条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.