CFlm25 mediated alternative polyadenylation regulates fibrosis in systemic sclerosis

CFlm25介导的选择性多聚腺苷酸化调节系统性硬化症中的纤维化

• 批准号: 10395959
• 负责人: Shervin Assassi
• 金额: $ 33.64万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-05 至 2024-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10395959
• 关键词: 3' Untranslated Regions; Address; Affect; Binding Sites; Biology; Bleomycin; Cells; Clinical; Collagen; Cutaneous sclerosis; Data; Deposition; Dermal; Diffuse Scleroderma; Disease; Distal; Down-Regulation; Event; Extracellular Matrix Protein Gene; Extracellular Matrix Proteins; FDA approved; Fibroblasts; Fibrosis; Genes; Genetic Translation; Goals; Human; In Vitro; Lead; Length; Link; Mediating; MicroRNAs; Modeling; Morbidity - disease rate; Mus; Myofibroblast; Names; Organ; Pathogenesis; Pathway interactions; Patients; Persons; Pharmaceutical Preparations; Poly(A) Tail; Polyadenylation; Production; Profibrotic signal; Prognosis; RNA; RNA Processing; Regulation; Repression; Research; Rheumatism; Sampling; Scleroderma; Site; Skin; Standardization; Systemic Scleroderma; Tail; Technology; Therapeutic; Time; Transcript; Transforming Growth Factor beta; Translations; Up-Regulation; Work; base; cleavage factor; cytokine; effective therapy; experimental study; gene repression; improved; indium-bleomycin; knock-down; mortality; mouse model; new therapeutic target; novel; protein expression; response; skin fibrosis; therapeutic target; transcriptome sequencing; translational study

Systemic sclerosis (SSc) is a multi-system, fibrotic disease that affects the skin and a variety of internal organs. Persistent myofibroblast activation and associated excessive extracellular matrix protein (ECMs) deposition are hallmarks of the disease. The mechanisms that account for this excessive fibrotic response remain elusive. Despite its high mortality and morbidity, there are no FDA approved medications for fibrotic complications of SSc. Our recent work indicates that a RNA-processing mechanism known as alternative polyadenylation (APA) is critical for the upregulation of profibrotic genes in dermal fibrosis through 3’ UTR tail shortening of key transcripts. Recent evidence demonstrated that a key regulator of APA is Cleavage factor Im 25 (CFIm25). The CFIm25 deletion leads to 3’ UTR shortening. A truncated 3’ UTR tail will often lack microRNA binding sites and evades the microRNA-mediated gene repression. Our preliminary data indicate CFlm25 is downregulated in fibrotic skin of SSc patients and in murine dermal fibrosis models. Knockdown of CFIm25 in normal skin fibroblasts is sufficient to promote the 3’ UTR shortening of key profibrotic genes. Moreover, the central fibrotic cytokine TGFβ suppresses CFIm25 expression through miR-203 upregulation. Overall, our data uncovered a novel mechanism by which TGFβ mediated CFIm25 downregulation leads to 3’ UTR shortening and the over-production of profibrotic factors and ECMs, and contributes to the pathogenesis of SSc. Based on this preliminary data, the main hypothesis of this project is that TGFβ and miR-203 downregulate CFIm25 in fibroblasts, resulting in dermal fibrosis by upregulation of profibrotic genes and ECMs through 3’ UTR shortening. This hypothesis will be examined in the following specific aims: Aim I: Define the fibroblast specific contribution of CFIm25 depletion in dermal fibrosis murine models. This aim will elucidate the downstream effects of CFIm25 depletion on key fibrotic pathways. Aim II: Determine the mechanisms for CFIm25 downregulation and assess their potential as therapeutic targets in dermal fibrosis. The mechanisms for TGFβ mediated miR-203 downregulation and subsequent CFIm25 repression by miR-203 will be elucidated. This aim will characterize the upstream events leading to CFIm25 depletion and will identify potential therapeutic targets. Aim III: Characterize CFIm25 in SSc human skin/fibroblasts and identify fibrotic genes dysregulated by APA. Serial dermal fibroblasts and skin samples from patients with early SSc and matched controls will be examined using a novel RNA sequencing technology. This aim will provide for the first time an unbiased, longitudinal view of CFIm25 mediated APA profile in a fibrotic disease. The proposed research links for the first time the CFIm25 mediated 3’ UTR shortening to dermal fibrosis. This can lead to discovering a key mechanism that amplifies the fibrotic response in SSc and ultimately to identifying an entirely novel target for treatment of persons with this potentially devastating disease.

系统性硬化症（SSc）是一种多系统、纤维化的疾病，影响皮肤和各种内脏