Biomarker Discovery in Muscles from FSHD Patients

FSHD是人类较常见的肌营养不良之一，具有非常罕见和少见的 了解生化、发育和分子基础。很明显的是，D4Z4重复 基因缺失以某种方式影响肌肉中基因的表达，从而导致 不同患者肌纤维变性程度不同，肌无力程度不同。我们已经确立了 通过对FSHD患者肌肉活检组织的蛋白质组学和RNA图谱分析，蛋白质和RNA 改变病变组织中的表达模式。此外，我们在5个FSHD家庭中观察到来自 巴西一些D4Z4缺失的无症状携带者大幅增加了12个基因的表达 包括4号染色体上编码的2个趋化因子，它们在症状性疾病中只有轻微变化 病人。我们建议跟进这些发现，并利用蛋白质、microRNA和mrna的表达。 侧写是了解不同疾病严重程度差异的一种方法 D4Z4缺失，希望这种理解可能会导致生物标志物的发现，这将是 有助于评估FSHD的潜在治疗方法。我们建议根据 以下具体目标：1)继续分析FSHD患者的mRNA，控制肌肉和细胞系 从不同的受累肌肉中产生，并通过RT-PCR确认现有的和新的阵列数据。2) 确认我们观察到的某些miRNAs在FSHD肌肉中的差异表达，并观察 我们观察到的miRNAs的预测靶标在来自 目标1.我们还将在肌源性细胞系中去除这些候选miRNAs，看看我们是否可以概括 培养我们在FSHD患者骨骼肌中看到的基因表达变化。3)最后，我们将继续 平行实验以确定FSHD肌肉和肌源性细胞系中蛋白质组的变化。

FSHD is one of the more common forms of muscular dystrophy in humans with a very unusual and poorly understood biochemical, developmental and molecular underpinning. What is clear is that the D4Z4 repeat deletion in some way influences the expression of genes in muscle in a dominant fashion to cause a variable degree of myofiber degeneration and muscle weakness in different patients. We have established by both proteomic and RNA profiling of muscle biopsies from FSHD patient that both proteins and RNA change expression patterns in diseased tissue. In addition, we have observed in 5 FSHD families from Brazil that some asymptomatic carriers of D4Z4 deletions substantially increase expression of 12 genes including 2 chemokines encoded on chromosome 4 which are only modestly changed in symptomatic patients. We propose to follow up on these findings and use protein, microRNA and mRNA expression profiling as an approach to understanding the differences in disease severity in different individuals with the D4Z4 deletion with the hope that this understanding might lead to the discovery of biomarkers which will be useful in evaluating potential treatments of FSHD. We propose to accomplish this goal according to the following specific aims: 1) Continue to profile mRNA from FSHD patients, control muscle and cell lines generated from differentially affected muscles and confirm existing and new array data by RT-PCR. 2) Confirm our observation on the differential expression of certain miRNAs in FSHD muscle and look at the change in expression of the predicted targets of our observed miRNAs in the mRNA expression arrays from aim 1. We will also ablate these candidate miRNAs in myogenic cell lines to see if we can recapitulate in culture the gene expression changes we see in skeletal muscle of FSHD patients. 3) Lastly, we will continue parallel experiments to define the changes in the proteome in FSHD muscles and myogenic cell lines.