Biological functions and post-transcriptional regulation of microRNAs

microRNA的生物学功能和转录后调控

• 批准号: 10919521
• 负责人: Katherine McJunkin
• 金额: $ 202.44万
• 依托单位: NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10919521
• 关键词: Address; Animals; Behavior; Biochemical; Biogenesis; Biological; Biological Process; Biology; CRISPR/Cas technology; Caenorhabditis elegans; Caffeine; Cell Lineage; Cellular biology; Cessation of life; Complex; Development; Disease; Embryo; Embryonic Development; Equilibrium; Exhibits; Family; Gene Expression; Gene Expression Regulation; Genetic; Malignant Neoplasms; Mediating; Messenger RNA; MicroRNAs; Modification; Molecular; Mutagenesis; Mutation; Names; Nucleotides; Organism; Phenotype; Physiological Processes; Plants; Play; Post-Transcriptional Regulation; Proteins; RNA Interference; Regulation; Research; Role; Stereotyping; Techniques; Therapeutic; Tissue Differentiation; Untranslated RNA; adenylate; forward genetics; genome editing; insight; member; model organism; mutant; next generation sequencing; novel; programs; tool; uridylate

MicroRNAs (miRNAs) are small noncoding RNAs that are loaded into Argonaute proteins to form the core of the miRNA-Induced Silencing Complex (miRISC). MiRNAs guide miRISC to complementary target mRNAs to silence their expression. Mutations in miRNA loci disrupt gene expression programs, and thus can contribute to the development of various diseases, including cancer. Consequently, understanding both the functions of miRNAs in normal development and the molecular mechanisms that regulate miRNAs are biological questions of critical importance. Understanding the biological functions of miRNAs during embryogenesis While the functions of miRNAs in differentiated tissues are well-studied in C. elegans and other organisms, the embryonic functions of only a few animal miRNAs are understood (reviewed in Kotagama, et al. 2023). C. elegans is an excellent model organism in which to study embryonic development due to its well-defined stereotypic cell lineage and powerful genetic tools. We are conducting forward (mutagenesis) and reverse (RNAi) screens for suppressors of microRNA family mutant phenotypes, currently focusing on the deeply conserved mir-51 family. We are also leveraging the power of CRISPR-Cas9-mediated genome editing to discover miRNA-target interactions that are essential to development (Yang, et al. 2020). Understanding the biological networks impacted by the embryonically-expressed microRNA families will yield important insights into how gene expression is controlled to coordinate embryogenesis. Defining the molecular mechanisms of miRNA and Argonaute turnover The balance of the rates of miRNA biogenesis and decay control miRNA abundance, and thus gene expression programs. Previous research has carefully elucidated mechanisms of miRNA biogenesis. However, we know very little about how miRNAs and miRISC are turned over either constitutively or in a regulated manner. This is a major gap in our understanding of miRNA regulation, and thus the regulation of gene expression. We previously demonstrated that Caffeine-Induced Death (CID-1) is necessary for uridylation of miRNAs, and F31C3.2 (which we named GLD-2 Related-2) is required for adenylation of miRNAs (Vieux, et al. 2021). We also found that these terminal modifications do not play a global role in influencing miRNA decay rates. More recently, we are investigating the regulated decay of the mir-35 family, which is essential for embryogenesis and sharply downregulated thereafter. This year, we showed that this miRNA family's decay is dependent upon its seed sequence (nucleotides 2-8), but not other parts of the miRNA sequence (Donnelly, et al. 2022). This represents a novel class of miRNA decay mechanism that may be harnessed therapeutically to modulate abundance of all redundant members of a miRNA seed family simultaneously.

MicroRNA (miRNA) 是一种小型非编码 RNA，可加载到 Argonaute 蛋白中，形成 miRNA 诱导沉默复合物 (miRISC) 的核心。 MiRNA 引导 miRISC 找到互补的靶 mRNA，以沉默其表达。 miRNA 位点的突变会破坏基因表达程序，从而导致包括癌症在内的各种疾病的发生。因此，了解 miRNA 在正常发育中的功能以及调节 miRNA 的分子机制是至关重要的生物学问题。 了解胚胎发生过程中 miRNA 的生物学功能 虽然 miRNA 在分化组织中的功能在秀丽隐杆线虫和其他生物体中得到了充分研究，但只有少数动物 miRNA 的胚胎功能得到了解（Kotagama 等人综述，2023）。秀丽隐杆线虫因其明确的定型细胞谱系和强大的遗传工具而成为研究胚胎发育的优秀模型生物。我们正在对 microRNA 家族突变表型的抑制子进行正向（诱变）和反向（RNAi）筛选，目前重点关注深度保守的 mir-51 家族。 我们还利用 CRISPR-Cas9 介导的基因组编辑的力量来发现对发育至关重要的 miRNA-靶标相互作用（Yang 等人，2020）。了解受胚胎表达的 microRNA 家族影响的生物网络将为了解如何控制基因表达以协调胚胎发生提供重要见解。 定义 miRNA 和 Argonaute 更新的分子机制 miRNA 生物发生和衰变速率的平衡控制 miRNA 丰度，从而控制基因表达程序。先前的研究已经仔细阐明了 miRNA 生物发生的机制。然而，我们对 miRNA 和 miRISC 如何组成性或以调控方式翻转知之甚少。这是我们对 miRNA 调控以及基因表达调控理解的一个重大差距。我们之前证明咖啡因诱导死亡 (CID-1) 对于 miRNA 的尿苷化是必需的，而 F31C3.2（我们将其命名为 GLD-2 相关-2）对于 miRNA 的腺苷酸化是必需的 (Vieux, et al. 2021)。我们还发现这些末端修饰在影响 miRNA 衰减率方面并没有发挥全局作用。最近，我们正在研究 mir-35 家族的受调控衰变，该家族对于胚胎发生至关重要，但随后急剧下调。今年，我们证明该 miRNA 家族的衰退取决于其种子序列（核苷酸 2-8），而不是 miRNA 序列的其他部分（Donnelly 等人，2022）。这代表了一类新型的 miRNA 衰减机制，可用于治疗性地同时调节 miRNA 种子家族所有冗余成员的丰度。

项目成果

The mir-35-42 binding site in the nhl-2 3'UTR is dispensable for development and fecundity.

nhl-2 3UTR 中的 mir-35-42 结合位点对于发育和繁殖力是不可或缺的。

• DOI: 10.17912/micropub.biology.000241
• 发表时间: 2020
• 期刊: microPublication biology
• 作者: Yang,Bing;McJunkin,Katherine
• 通讯作者: McJunkin,Katherine

The E3 ligase Poe promotes Pericentrin degradation.

• DOI: 10.1091/mbc.e22-11-0534
• 发表时间: 2023-08-01
• 期刊: MOLECULAR BIOLOGY OF THE CELL
• 影响因子: 3.3
• 作者: Galletta, Brian J.;Varadarajan, Ramya;Fagerstrom, Carey J.;Yang, Bing;Haase, Karen Plevock;McJunkin, Katherine;Rusan, Nasser M.
• 通讯作者: Rusan, Nasser M.