The Genomic Analysis of Erythrocyte microRNA in Sickle Cell Diseases

描述（由申请人提供）：人类红细胞（红细胞）疾病，包括贫血和疟疾，对人类造成巨大负担。我们对这些疾病的了解相当有限。例如，虽然镰状细胞病（SCD）的遗传原因和疟疾感染对它们的正选择早已确定，但关于SCD红细胞表型如何导致不同的临床表现和改变与疟疾寄生虫的相互作用，仍有许多有待了解。人成熟红细胞被认为缺乏大多数RNA表达。通过捕获小分子RNA的方法，我们发现人类成熟红细胞中仍然含有丰富多样的microRNA（miRNAs），这是一类具有重要调控功能的21-23个核苷酸的非编码RNA。鉴于miRNA在红细胞生成过程中的潜在调节作用，红细胞miRNA库可能包含重要的生物学信息，指示发育历史，并显示红细胞的生物学表型。用miRNA微阵列分析miRNA表达确实揭示了正常红细胞和SCD红细胞之间的显著差异。红细胞miRNAs也可能在成熟红细胞中发挥功能性作用。已经发现在红细胞内感染期间，几种miRNAs易位到疟原虫中。这些转移的miRNAs破坏疟疾寄生虫的生长和复制。我们推测，与正常红细胞相比，SCD红细胞中miRNA表达的改变可能有助于其对疟疾感染的易感性降低。在这个提议中，我们计划应用基因组学工具和先进的生物信息学来研究miRNA作为SCD表型和疟疾易感性的遗传决定因素的作用。在第一个具体目标中，我们将鉴定红细胞miRNA，其表达可以区分正常红细胞、不同SCD亚型和其他贫血疾病。这些miRNAs的鉴定将对贫血疾病具有诊断价值，并导致对相关潜在病理生理机制的新见解。在第二个目标中，我们将确定不同类型的红细胞之间miRNA组成的差异是否有助于它们对疟疾感染的不同易感性。这些实验的完成将导致更好地理解miRNA在血红蛋白病和感染性疾病中确定红细胞表型的作用，并为SCD和疟疾感染提供更好的治疗策略。公共卫生相关性：在这个题为“镰状细胞病中红细胞microRNA的基因组分析”的提案中，我计划使用新的基因组工具和先进的生物信息学来分析镰状细胞病中红细胞microRNA的含量。我们希望我们的研究将确定红细胞microRNA在告知红细胞表型和镰状细胞疾病的临床表现中的作用。我们还将确定红细胞microRNA的作用，在体外确定恶性疟原虫之间的正常和镰状红细胞的易感性。

DESCRIPTION (provided by applicant): Human red blood cell (erythrocyte) diseases, including anemia and malaria, pose a huge burden for the human race. Our understanding of these diseases is rather limited. For example, while the genetic cause of sickle cell diseases (SCD) and the positive selection of them imposed by malaria infection have been long established, much remains to be learned about how SCD erythrocyte phenotypes contribute to diverse clinical manifestations and to altered interaction with malaria parasites. Human mature erythrocytes are thought to lack most RNA expression. With a procedure capturing small-sized RNAs, we have found that human mature erythrocytes still possess abundant and diverse microRNAs (miRNAs), a class of 21-23 nucleotide non-coding RNA with important regulatory functions. Given the potential regulatory roles of miRNAs during erythropoiesis, the erythrocyte miRNA pool is likely to contain important biological information, indicate developmental history, and show biological phenotypes of erythrocytes. The analysis of miRNA expression with miRNA microarrays indeed reveals a dramatic difference between normal and SCD erythrocytes. Erythrocyte miRNAs may also play a functional role in the mature erythrocyte. Several miRNAs have been found to be translocated into malaria parasites during intraerythrocytic infection. These transferred miRNAs disrupt the growth and replication of malaria parasites. We hypothesize that the altered miRNA expression in SCD erythrocytes compared to normal erythrocytes may contribute to their decreased susceptibility to malaria infection. In this proposal, we plan to apply genomic tools and advanced bioinformatics to examine the role of miRNAs as genetic determinants of SCD phenotypes and malaria susceptibility. In the first specific aim, we will identify erythrocyte miRNAs whose expression can distinguish between normal erythrocytes, different SCD subtypes, and other anemia disorders. The identification of these miRNAs will hold diagnostic value for anemia disorders and lead to fresh insights into relevant underlying pathophysiological mechanisms. In the second aim, we will determine whether the differences in miRNA composition among different types of erythrocytes contribute to their differing susceptibility to malaria infection. The completion of these experiments will result in a better understanding of the role of miRNAs in determining erythrocyte phenotypes in hemoglobinopathies and infectious diseases as well as provide better therapeutic strategies for SCD and malaria infection. PUBLIC HEALTH RELEVANCE: In this proposal titled "The Genomic Analysis of Erythrocyte microRNA in Sickle Cell Diseases", I plan to use novel genomic tools and advanced bioinformatics to analyze the erythrocyte microRNA contents in sickle cell diseases. We expect that our study will determine the role of erythrocyte microRNAs in informing the erythrocyte phenotypes and clinical manifestations of sickle cell diseases. We will also define the role of erythrocyte microRNA in determining the in vitro susceptibility to Plasmodium falciparum among the normal and sickle erythrocytes.